The 7ra/ity die casting......... casting............................ ....................................... .............................................. ........................................ ................ 23 The Vacuu# Vacuu# die casting................. casting..................................... ....................................... ..................................... ................................ .............. 24 Chapter 4: Die Casting *achine......................................... *achine.......................................................................... ...................................... ..... 2% Considerations when buying die casting machines ............................................................2%
The pressure pressure die die casting #achines.................. #achines...................................... .............................................. ................................. ....... 2( The gra/ity die die casting #achine................... #achine....................................... ......................................... ................................... ................ 2) Die casting #o$d............................. #o$d................................................. .......................................................... .................................................. ............ 2+ What determines a quality die casting mold? ...................................................................2+
Chapter : Die Casting rocess............. rocess................................. ....................................................... ............................................... ............ 3ressure ressure die casting process.............................. process.................................................. ........................................ ............................... ........... 37ra/ity die casting process.......................... process.............................................. ..................................................... ..................................... .... 31 Chapter %: Die casting app$ications..................... app$ications........................................ ....................................... .................................. .............. 31 0pp$ications o &rass die casting........................................... casting........................................................................ ............................. 31 0pp$ications o a$u#inu# die casting.............................. casting................................................. ...................................31 ................31 0pp$ications o 'inc die casting............................................. casting.................................................................... ............................. ...... 32 0pp$ications o stee$ die casting.............................................. casting......................................................................... ...........................32 32 0pp$ications o copper a$$oys................................................ a$$oys.................................................................... .............................. .......... 32 Chapter (: The 0d/antages Die Casting........................ Casting................................................. ...................................... ............. 33 Chapter ): Die Casting Deects........................... Deects............................................... .................................. ............................. ................... .... 34 Chapter +: Die Casting 0ssociation................... 0ssociation....................................... ................................. ........................... ...................... ........ 3 The North America Die Casting Association Association (NADCA) ........................................................3% The Canadian Die Casters Association Association ..............................................................................3% The Die Casting ociety ...............................................................................................3%
Introduction Die casting is an important manu!acturing technology used in many industries" Companies can ma#e nearly all parts using di!!erent casting processes" $n this e%oo#& we shall e'plain eerything you need to #now about die casting& metal alloys& die casting techniques and its 2
The 7ra/ity die casting......... casting............................ ....................................... .............................................. ........................................ ................ 23 The Vacuu# Vacuu# die casting................. casting..................................... ....................................... ..................................... ................................ .............. 24 Chapter 4: Die Casting *achine......................................... *achine.......................................................................... ...................................... ..... 2% Considerations when buying die casting machines ............................................................2%
The pressure pressure die die casting #achines.................. #achines...................................... .............................................. ................................. ....... 2( The gra/ity die die casting #achine................... #achine....................................... ......................................... ................................... ................ 2) Die casting #o$d............................. #o$d................................................. .......................................................... .................................................. ............ 2+ What determines a quality die casting mold? ...................................................................2+
Chapter : Die Casting rocess............. rocess................................. ....................................................... ............................................... ............ 3ressure ressure die casting process.............................. process.................................................. ........................................ ............................... ........... 37ra/ity die casting process.......................... process.............................................. ..................................................... ..................................... .... 31 Chapter %: Die casting app$ications..................... app$ications........................................ ....................................... .................................. .............. 31 0pp$ications o &rass die casting........................................... casting........................................................................ ............................. 31 0pp$ications o a$u#inu# die casting.............................. casting................................................. ...................................31 ................31 0pp$ications o 'inc die casting............................................. casting.................................................................... ............................. ...... 32 0pp$ications o stee$ die casting.............................................. casting......................................................................... ...........................32 32 0pp$ications o copper a$$oys................................................ a$$oys.................................................................... .............................. .......... 32 Chapter (: The 0d/antages Die Casting........................ Casting................................................. ...................................... ............. 33 Chapter ): Die Casting Deects........................... Deects............................................... .................................. ............................. ................... .... 34 Chapter +: Die Casting 0ssociation................... 0ssociation....................................... ................................. ........................... ...................... ........ 3 The North America Die Casting Association Association (NADCA) ........................................................3% The Canadian Die Casters Association Association ..............................................................................3% The Die Casting ociety ...............................................................................................3%
Introduction Die casting is an important manu!acturing technology used in many industries" Companies can ma#e nearly all parts using di!!erent casting processes" $n this e%oo#& we shall e'plain eerything you need to #now about die casting& metal alloys& die casting techniques and its 2
applications" $t is designed to gie a comprehensie co mprehensie oeriew and details about all you need to #now about die casting"
Chapter 1: Die casting defnition This section is designed to introduce the reader to the basic concepts o! die casting" c asting" This !irst chapter coers a comprehensie de!inition about die casting& the necessary ideos to watch and die casting e'amples" %y the end o! this chapter& you should be able to understand the !ollowing #ey !actors *" Di!!erenti Di!!erentiate ate die casti casting ng !rom other metal casti casting ng processes processes +" ,nderst ,nderstand and the the hist history ory o! o! die die castin casting g -" .eature .eaturess o! die castin casting g mater material ialss
What is die casting? To begin with& we need to understand what metal casting is" According to The /ngineer0s 1andboo# & this is a manu!acturing process where solid metals are melted and heated to a desired d esired temperature a!ter which& it is poured into a caity ca ity or mold with proper shape" The melting and heating process may require di!!erent !urnace heating temperatures" 2oreoer& di!!erent chemical substances may be added to modi!y the chemical composition o! the metal" $t is this mold that contain the desired shape and si3e" The process may be a single step o! a series o! steps depending on the comple'ity o! the metal substance" The !inal product can hae irtually any si3e depending on what the designer desires" The cast parts may range !rom !raction o! inches to oer -4 !eet" $t will depend on the design o! the mold or the end product" Apart !rom these& it is also crucial to highlight the ma5or metal casting p rocesses that hae been used in this industry" These include *" +" -" 6" 4"
and and cast castiing $ne $nest stme ment nt cast castin ing g Lost Lo st Wa Wa' cast castin ing g 7erm 7ermane anent nt mo mold ld cast castin ing g Cent Centri ri!u !uga gall cast castin ing g
What makes die casting a distinct and more importantly intriguing?
All the other process $ hae listed aboe are collectiely re!erred to as 8!oundry processes9 e'cept die casting" Let0s 3ero in to what die casting is" The /ngineering"com /ngineering"com de!ines de!ines die casting as a manufacturing process that produces metal parts The of virtually all designs by forcing molten metal under high pressure into a die cavity. The underlying !actor here is exerting high pressure pressure through a die. $t is a #ey !actor that distinguishes this metal !abrication process !rom the other metal casting procedures listed aboe" 3
.or instance& i! we loo# at a processes such as lost wa' casting& inestment casting and sand casting procedures: the underlying !actor in this case is the !act that& the process depends on gravity to !ill the mold" The Cambridge Dictionary de!ines gravity as a natural !orce that attracts ob5ects towards one another& more so that !orce& which ma#es things !all on the ground" This !urther reeal more properties o! die casting in relation to other metal casting processes" 1ere are the #ey points to note here *" The metal die casting process has a short cycle time +" The metal !low is !aster in die casting due to e'istence o! e'ternal !orce -" The molds in die casting are not as thic# as those used in the sand casting or inestment casting processes The metal die casting process& is used to produce arious shapes !rom a number o! non;!errous metals such as brass (an alloy)& 3inc& aluminum& magnesium and copper among other metals" $t is one o! those manu!acturing processes with the ability to produce high detailed and accurate parts" $t is also pre!erred !or mass production o! components as opposed to other manu!acturing processes" Ta#e !or instance& the !aucet parts& door #nobs& decoratie parts& etc"
The history o die casting The history o! this manu!acturing technique could be traced bac# to the *==>s" $t was during this time that a patent was awarded to turges in *=6" This was a!ter the inention o! a manually operated machine that was used !or the casting printing type" +> years later& the technology was mainly used !or tin and lead" This was be!ore the technique was used !or other metals such as aluminum and 3inc in the *+>s" ince then& there are a number o! technological adancements that hae been witnessed in the industry" This include a number o! metallurgical control measures that hae improed the manu!acturing and processing criteria" The technological adancements !ocus on the !ollowing #ey aspects *" $ncreasing the die casting capacity& thus higher production@short production runs +" ophisticated die construction processes -" An adanced casting capability with a number o! metals such as steels and brass being included in the process The eolution too# place so !ast that by +>>4& in North America alone& the total number o! sales !or die cast products was about = billion" Apparently& this number has doubled with most manu!acturers !ocusing on arious alloys" This is due to the high demand in the o!!ice equipment& sporting& toys& machinery& automotie and many other applications o! dis cast parts and components" A number die casting !actories that hae !ocused on arious niches in the industry" .or e'ample& there are 4
*" The captie die casting companies: these are companies that produce components !or their own use" A good e'ample is the B2 metal casting plant in %ed!ord" According to the $nside $ndiana %usiness& the company has inested more than *+ million in its %ed!ord Casting perations" +" The custom die casting companies mainly !ocus on producing the die cast parts !or their company" This is mainly !or the original equipment manu!acturer (/2)" ne such company is the Chinese Company& Batonbrass" $t has !ocused on brass lamp& electrical& !urniture& plumbing and home accents& among other parts" o& what should we learn !rom this section? Eou should be able to distinguish die casting !rom other metal casting processes and a #e y point to note is& the process requires some induced pressure" $t is an old manu!acturing technique that dates bac# to *==>s and has eoled oer time" Lastly& it has been adopted in a number o! industrial setups with companies such as B2 and Batonbrass" This clearly shows how important the entire process is" To get insights on die casting& and the practical aspect o! the process& we need to !ocus on the actual procedure" This will be e'plained through the ideos in the ne't section o! this chapter"
The Die Casting Videos These die casting ideos will try to gie an insight on the basic !actors about this manu!acturing process" Benerally& this a practical process that neither die casting technicians nor pro!essionals must not depend on the theoretical part o! it" The understanding should be based on both the theoretical aspects& watching ideos and implementing the #nowledge one gets" %elow are 4 die casting ideos you should hae a loo# at https@@www"youtube"com@watch?F75Gm55,Had= This ideo e'plains the most basic !orm o! die casting" The #ey parts that are inoled& how arious parts moe until we obtain the !inal product I die cast part" /en thou there are di!!erent machines in the industry& the principle o! operation is still the same" https@@www"youtube"com@watch?FWJ
This is a ital ideo !or companies that would wish to inest in the die casting manu!acturing process" They0ll be able to understand the choice o! machines and the reason as to why they need either go !or a hori3ontally or a ertically hydraulic operated machines" Alternatiely& i! they should opt !or the cold or hot chamber machines"
https@@www"youtube"com@watch?FL!
The Die Casting !"a#p$es Die casting is one #ind o! technology that we hae lied to embrace in our day;to;day actiities" This is a popular manu!acturing process that is used to produce a number o! metal parts both !or industrial and domestic applications" .or this particular section& we0ll categori3e these parts based on where they are used i"e" their industrial or domestic applications" The most common die casting e'amples include the !ollowing
The &rass parts These are common e'amples o! die cast parts that we meet in our daily lies" They are aailable in di!!erent con!igurations" These lamp parts include brass !i'ture body parts& nec#s and brea#s amongst others"
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Examples of brass lamp parts With these designs& you can easily ma#e your own custom lighting !i'tures" %e it a custom !loor or table lamp" $t doesn0t matter whether you need antique lighting !i'ture or one that can meet the unique requirements o! your house"
ther brass pars may include *" The brass electrical components such as the soc#et termination parts and coa'ial cables" +" 2echanical parts such as those that are used in the plumbing industry" These may include pipe 5oints& washers& nuts& !langes and T;5oints 5ust to mention a !ew" -" The house accents such as brass candle holders& ases& canisters& decoratie pillows& etc" 6" The !urniture hardware such as door #nobs& loc#s and handles" 4" The brass precision components such as clips& connectors and taps among other sections"
The 'inc cast parts Minc is also a popular metal that is used in this industry" Normally& the manu!acturers hae to choose between the MA and MA2A alloy" The choice o! any alloy will depend on the desired physical properties o! the end product" That is& parts cast using the MA alloys hae superior strength due to high mounts o! aluminum" The Mama# alloys o!!er better castability"
The zinc cast components
The cast parts may include window hardware& electrical components& bathroom !i'tures and o!!ice equipment& 5ust to mention a !ew" (
The stee$ cast parts Li#e the other metals mentioned aboe& the steel cast parts also !orm an integral role o! our lies" This inoles casting di!!erent types o! steels such as stainless steel" ome o! the most common components that are manu!actured ia this technique include ales& hydroelectric turbine wheels& tooling equipment and pumps among other parts in !ood& electrical and power industries" All these parts must be manu!actured as per the international standards and regulations"
The steel cast components
The iron cast parts This inoles casting a number o! iron carbon alloys" These metals hae a carbon content that is more than +O" Again& the iron casting company should be able to choose that speci!ic metal that can meet the requirements o! the end users" This inoles determining the carbon content& iron and silicon content" %elow are images o! the iron cast parts
Examples of iron cast components
The a$u#inu# cast parts %oth aluminum and aluminum alloys are commonly used to cast di!!erent machine components" These alloys contain di!!erent elements such as copper& manganese& magnesium& silicon and 3inc& )
5ust to mention !ew" These elements e'ist in di!!erent proportions thus& di!!erent procedures can be used to cast the aluminum parts" These parts are used in di!!erent industries such as aerospace& electronics& plumbing and chemical industries"
Examples of aluminum cast components
$n summary& there are ery many types o! components and structured that can be manu!actured through die casting" $t is upon the end user to choose that #ind o! metal he@she desired !or a gien application" 1oweer& some may require additional secondary operations" A!ter this section& you should be able to list the arious components or industries that depend on brass die cast components"
Chapter 2: Die Casting *ateria$s Not all metals or alloys can be die cast" This is due to the arying chemical and physical properties" As we all #now& die casting inoles heating the metal until it melts and !orcing it under pressure into re;usable molds" .irst& we need to understand two aspects here *" 1eating a metal to a desirable melting temperature: there!ore& the metal should be able to maintain its desirable characteristics within that temperature range& otherwise& the whole process will be !utile" +" /'erting pressure& the metal must be able to maintain the same properties when sub5ected to these high pressures" $n this chapter& we shall discuss the arious materials that can be manipulated through this manu!acturing technique" This will act as a guide to enable the readers choose the right material !or a speci!ic application" 2oreoer& they should be able to adopt the right die casting technique based on the chemical and physical properties o! the metals or alloys" +
$deally the main die casting alloys that are commonly used in industries include 3inc& magnesium& tin& lead& aluminum and copper" 1oweer& !or the purpose o! this e%oo#& we shall !ocus on the !ollowing #ey materials 3inc& aluminum& brass and steel"
The Die Casting *ateria$ ,e$ection Criteria This should be based on research and not a trial and error or unapproed theories" $t is through a proper understanding o! each metal or metal alloy that one will be able to choose the right material and die casting technique" As matter o! !act& these alloys and metals hae di!!erent mechanical and physical properties" This e'plains the reason why they react di!!erently when sub5ected to certain manu!acturing processes" $t is adisable to wor# closely with e'perts to establish the right material !or any gien application" This may inole a simple comparison process that may b e simpli!ied as *" $t is ital to consider all the ital mechanical properties o! those materials" This is what we shall also e'pound on eery material" The ital mechanical properties include elongation& tensile strength& hardness& impact strength and yield strength" These will be based on actual tests" +" The physical properties o! the metal alloy: it is important to understand the behaior o! the metal when sub5ected to e'treme enironmental conditions" These may include high temperature or e'treme stress and heat" -" $t is ital to e'amine and understand the composition o! the alloys" This should be based on the basic composition o! indiidual element and their uses" $n short& these three aspects will help you to narrow down to that speci!ic alloy or metal that can meet the desired application requirements" This should be a per!ect comparison that aims at getting the best material !or die casting" 1aing noted& all these& let0s e'plore the aailable options" %elow are the most common materials that you can die cast
inc Die Casting Minc is one o! the most popular metals that is used to ma#e a number o! products" Li#e other metals& casting 3inc requires that one understands its basic alloys" The aailable 3inc alloys can be categori3ed as *" The MA alloys: these alloys are mainly used to cast components that require superior strength" This strength is due to the !act that they contain higher amount o! aluminum" +" The Mama# alloys: these alloys contain about 6O aluminum" Li#e the MA alloys& they are #nown to hae proide good castability and strength" .or decades& these alloys hae been used in ma5or metal casting applications" Li#e other die casting technologies& this process inoles !orcing the molten 3inc under high pressure into a mold caity"
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The 3inc cast parts are used in a wide range o! applications that impact our daily lies" $t is worth noting that 3inc casting contribute a lot to the global economy" This ranges !rom creating employment to the !inished products that we use in our daily lies" We use these products both !or !unctional and decoratie applications"
The ad/antages o 'inc die casting $deally& these are the basic !acts that ma#e 3inc the best choice !or a number o! manu!acturing processes" pting !or 3inc alloys should be designed !or indiiduals who wish to achiee the !ollowing #ey aspects Process flexibility
This is a critical aspect in the metal alloy processing industry" The 3inc alloys can be die c ast to any shape o! choice" This is actually the main reason why it is used !or both high quantity and quality production processes" Precisions and tolerance
This eliminates any additional machining operations that would otherwise increase the production costs" This is due to the !act that 3inc alloys can be die cast to closer tolerances that other metal alloys" %asically& this implies that the !inal product will be e'act component that is desired" Strength and ductility
A number o! plumbing or machinery component are die cast" Minc alloys can withstand ery e'treme pressure I as high as J>&>>> psi" Due to its ductility& the end products are suitable !or rieting& bending and crimping operations" Again& it is also worth noting that the 3inc alloy is tougher than most metal alloys" Excellent thermal properties
These die cast parts possess desirable electrical conductiity" This is the main reason why they are used !or electrical components such as heat s#in#s or any other application that requires an electromagnetic shielding" Apart !rom the properties listed aboe& it is worth mentioning that other properties o! die cast 3inc parts also possess the !ollowing #ey !eatures e'cellent rigidity& anti;spar#ing& good bearing properties& easy !inishing& thin wall castability& long tool li!e& recyclable and ease to machine"
0pp$ications o 'inc die casting As mentioned aboe& the die casting process produces structures with a number o! superior chemical and physical properties" This is actually one o! the main reasons why the process is popular across ery many industries" Benerally& the 3inc cast parts are mainly used in the !ollowing #ey applications
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*" To manu!acture comple' metal parts: this is due to the !act that it is easier to manu!acturer items that are accurate with ery tight tolerances" 2oreoer& this is also attributed to the !act that the 3inc can be manipulated to a wide range o! shapes" +" These alloys are also used to manu!acture parts that should be wear resistance with the ability to maintain high structural integrity" This is essential in the electrical and automotie industry" -" The !act that 3inc alloys can be used to manu!acture ery thin parts ma#es it a per!ect choice !or a number o! consumer products& especially the consumer electronics" $n summary& as we wind up this section& there are a !ew things you n eed to note and these include *" Eou should be able to choose the right 3inc alloy !or any die casting process +" ,nderstand the basic properties that ma#e 3inc alloy a per!ect choice !or a gien application"
0$u#inu# die casting ince aluminum was discoered oer +>> years ago& it has remained to be one o! the most abundant metal" $t used !or a wide range o! engineering applications and it can be manipulated to any shape depending on the requirements at hand" Apparently& die casting aluminum has proed to be enironmentally and sustainable" This is !rom the !act that about 4O o! the metal can be recycled" This reduces the amount o! waste in the enironment" $n !act& it is a non;!errous metal that is commonly die cast in the world today" Again& die casting aluminum is generally cost e!!ectie" This is basically due to the intrinsic physical and chemical properties o! aluminum" This is the main reason why it has been adopted globally" To decide whether to use aluminum alloys !or a particular application& you need to understand the basic physical and chemical properties" This !orms and integral part when it comes to decision ma#ing"
Characteristics o a$u#inu# a$$oys This is a ersatile metal with a wide range o! desirable physical and chemical properties" This is actually the reason why the aluminum die cast parts are used in a number o! domestic and industrial applications" ome o! these properties include Superior corrosion resistance: this e'plains the reason why these die cast parts are used in chemical and petroleum industries" This metal cannot be attac#ed by most organic and inorganic compounds" This is due to the !act that it reacts with atmospheric air to !orm a thin o'ide layer that is inert" $n some instances& the die cast parts can be processed using the electrolytic o'idation process"
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Lightweight : it has an aerage density o! +"> g@cm-" The aluminum alloys are some o! the lightest alloys aailable" This implies that the die cast components can be used in applications where the oerall weight o! the product should be reduced as much as possible" They are commonly used in the aerospace industry" Superior thermal and electrical properties: this is due to its position in the periodic table" Aluminum has an o'idation no" P-" $t as !ree electrons that can conduct electricity and thermal energy" This is actually the main reason why they !orm a per!ect alternatie !or copper" $ts electrical conductiity can be estimated to about -J m@hm mmQ" High operating temperature: this is the main reason why the die cast aluminum parts can be used in a number o! electrical applications" These include heat sin#s& electrical connectors& thermometer coers& etc" This is also the main reason why the die cast parts are used as utensils" n aerage& the aluminum alloys hae a melting point o! about JJ> RC" Strength and hardness: generally& the aluminum alloys are sti!! with superior strength to weight ratio" This e'plains the reason why they can be used as rails" Environmentally friendly: these metals are !ully recyclable thus& reducing the scrap metal in the enironment" !" and E#" shielding properties: this is the main reason why they are used in electrical components where these radiations may reduce or inter!ere with the systems per!ormance"
$n addition to these& the aluminum alloys also possess superior sur!ace !inish" %lending all the aboe properties together& the designers are always sure o! a die cast aluminum part with superior per!ormance" This is the main reason why these die cast parts are used in the !ollowing industries
0pp$ications o a$u#inu# a$$oys ince we hae highlighted a number o! applications when discussing the characteristics o! these metals& we shall list the arious industries and speci!ic components that are manu!actured !rom these alloys" 1oweer& you should note that this list may not be e'haustie" These industries include *" They are used in the automotie and aerospace industry" This is because their lightweight contribute signi!icantly in !uel e!!iciency" +" They are used in electrical& thermal and electronics industries" This is due to superior electrical and thermal properties and good shielding properties" The die cast aluminum can be used as electrical connectors in the high temperature applications" -" The die cast parts are used in networ#ing in both computers and communication industries" This is because they can dissipate heat and act as the radio !requency !ilter" Again& they proide a good K.$@/2$ shielding ma#ing a per!ect choice !or a number o! handheld deices"
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$n short& it is irtually impossible to lie without the die cast aluminum parts" Again& we need to note that there are di!!erent types o! alloys optimi3ed !or di!!erent applications" This ma#es it crucial to discuss the aluminum alloys as essential die casting materials" This will also help when it comes to deciding on the #ind o! materials one should opt !or"
Types o a$u#inu# a$$oys or die casting app$ications $n this e%oo#& we shall !ocus on di!!erent types o! aluminum alloys that are die cast in most industrial setup" These alloys include the !ollowing The $%alloy: this aluminum allow is #nown to possess the !ollowing #ey properties resistance to corrosion& improed cooling and 3ero post die casting operations" &lloy '(): superior die casting properties and it possess good !luidity and guarantee better pressure tightness" &lloy )*): it possesses the !ollowing #ey properties dimension stability& ease o! casting and good mechanical properties" $t has superior corrosion resistance too" &lloy +),-: it is #nown !or its superior wear resistance and high hardness" They are mainly used to die cast the internal combustion engine pistons" The &)-: it is mainly used to cast aluminum parts where pressure tightness and !luidity is a priority" $t maintains corrosion resistance and strength een at eleated temperature" &lloy &'(): its properties are similar to that o! the alloy A-J>" This alloy is mainly used to die cast hydraulic cylinder components" &lloy &)*-: it has good thermal and mechanical properties" $ts per!ormance properties is similar to most alloys listed aboe"
$n summary& by the end o! this section& you need to understand the basic properties o! all the possible aluminum die casting alloys" This is important when you need a speci!ic aluminum alloy !or a gien application"
rass die casting %rass& is an alloy o! mainly copper and 3inc" %y arying the amount o! copper and 3inc in the !inal product (brass)& we are able to obtain di!!erent types o! brass alloys" Choosing a gien type o! alloy will depend on the primary ob5ecties one intends to reali3e" $n most cases& the standard brass may hae about JO o! copper and --O o! 3inc" Normally& these metals may not proide the desired per!ormance properties o! brass& thus& other metal elements can be added" This basically aims at incorporating the desired !eatures" .or instance& lead can be added to the alloy (about +O) to improe the machinability property o! brass" This implies that& without lead& then it will be di!!icult to die cast brass"
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$n this section& we shall !ocus on the main properties that we need to consider when we want to choose brass alloy !or any gien applications" This implies that& we shall discuss the characteristics@properties& applications and types o! brass alloys" With this in!ormation& we should be ma#e the right decision as !ar as choosing the right metal is concerned"
Characteristics o die cast &rass The die cast brass possess the !ollowing #ey characteristics or properties Easy to machine/die cast : this is an important property o! brass" 2etals that are cumbersome to die cast will result in high production cost" $t is important to no te that brass is not inherently easy to machine" Adding about +O o! lead enhances the machinability properties" Lead is a per!ect choice !or this application since it has a low melting point than both copper and 3inc"
$n some instances& silicon can be used instead o! lead" 1oweer& brass alloys with silicon must not be mi'ed with the ones haing lead" 0orrosion resistance: brass alloys can be modi!ied to o!!er high leel o! corrosion resistance" A good e'ample is the de3inci!ication resistant (DMK) brass" $t will remain e!!ectie and reliable een in harsh enironmental conditions" They can resist aggressie enironmental conditions"
This is the main reason why the die cast brass parts are used in plumbing systems with high temperature or high concentration o! chloride" Die casting these parts require care!ul manu!acturing process" This is crucial when it comes to balancing the desired metal elements" Low melting temperature: this ma#es die casting brass a cost e!!ectie process" The melting point o! brass is about >> R0. This implies that less energy will be required to melt and subsequently process it to obtain the desired shapes" +right or gold li1e appearance: this ma#es it a per!ect choice !or most decoratie applications" The brass parts that hae been die cast are used to ma#e door #nobs& window loc#s& !lowers ases& bearings& etc" The brass cast parts are e'tensiely used in a number o! electrical& musical instruments and plumbing applications" $ts color& which tend to resemble that o! gold ma#es the brass die cast components resistant to tarnishing" Low co%efficient of friction2 brass is generally so!t thus& it can be used to ma#e die cast parts that do not require !riction" These include bearings and !ittings" elatively strong : a gien quantity o! aluminum can be added to improe its strength" The die cast brass parts with a thin layer o! transparent aluminum are sel!;healing" Tin also seres the same purpose" A reason why it is a per!ect choice !or the brass parts used in water applications such as the naal brasses" Environmentally friendly: nearly >O o! brass cast parts can be recycled" This ma#es it a sustainable metal as it reduces the amount o! scrap metal" This is due to the !act that brass is a non%ferromagnetic metal" This ma#es the separation process easy I by using a magnet" 1
$n summary& !rom these properties& you can easily e'amine the situation at hand and decide whether to adopt brass die cast parts o! not" o& what are the main applications o! brass die cast components?
0pp$ications o &rass die cast parts %ased on the aboe properties& we can summari3e the #ey applications o! brass die casting as *" +" -" 6" 4" J"
7arts that should be resistant to corrosion e"g" marine@salty water applications Kesistance to aderse temperature e"g" pipes carrying hot water or gas uperior electrical conductiity e"g" soc#et terminals and electrical parts Withstand high pressure (about ->>psi) e"g" pressure pipes Decoratie components e"g" lamp parts and !urniture hardware Abrasion resistance or low co;e!!icient o! !riction"
$n short& brass is a ersatile alloy that can be used !or nearly all applications" $t is upon the end user to e'amine the requirements o! the application at hand" Another demanding process is to determine the right brass alloy" That is& one that meets the required application o! a gien die casted part" Let0s e'plore the arious brass alloy types
Types o &rass a$$oy used in die casting There are ery many types o! brass alloys" This is based on the basic constituents o! the alloy alongside the primary elements (copper and 3inc)" The ariation in their constituents ma#e the alloys suitable !or di!!erent applications" This basically calls !or critical analysis and ealuation o! eery aspect be!ore deciding on a speci!ic alloy to go !or" ome o! the most common brass alloys include *" Admiralty brass: it is mainly used in applications where de3inci!ication is a problem" $t is made o! 3inc& copper and tin" +" AichSs alloy: it is mainly used in marine applications" This is due to its high corrosion resistance" The main constituents include copper& 3inc& tin and iron -" Alpha brass: they are mainly used in pressing applications" They hae less than -4O 3inc" 6" Duple' brass: it has and US phase and it contains between -4 to 64O o! 3inc" 4" Aluminium brass: they0re mainly used to cast brass parts that should be resistant to corrosion" They contain aluminum" J" Arsenical brass: the die cast parts !rom this brass alloy are mainly used in boiler !irebo'es" " %eta brass: they can be die cast easily" They contain between 64 and 4>O 3inc" =" Cartridge brass: they are mainly used to ma#e ammunition cases and the hae ->O 3inc" " Kiet brass: it contains -O 3inc" *>" DMK brass: contain arsenic and ery resistant to most weather conditions" **" Ked brass: it contains =4O copper with the other three elements (tin& 3inc and lead) aailable in same proportion (4O each)" *+" Kich low brass: it is mainly used to cast 5ewelry" $t contains *4O 3inc" *-" White brass: contains more 4>O 3inc and it0s also brittle" 1%
*6" Eellow brass: contains --O 3inc" As you can see& there are ery many alloys o! brass that you can die cast" This actually ma#es it di!!icult to choose the right alloy !or a speci!ic application" This is why you need to get an e'pert in the die casting materials" $t is quite eident that all these ariations are as a result o! arying the main constituents o! these metal elements" $n summary& by the end o! this section& you should be able to ealuate all the aailable types o! brass alloy" This should be based on the desired per!ormance requirements" This is actually the -rd material that we hae discussed" Note that the properties@characteristics o! the material is a determinant !actor here" Eou need to understand it to ma#e the right decision" The last material in this category is the
,tee$ die casting Li#e other metals& steel is also a common metal that can be die cast" This is due to its ersatility and !unctionality" $t is also important to ealuate the arious characteristics@properties& applications and types o! steel aailable" This is will !orm the !oundation o! any steel die casting process" teel itsel! is an alloy o! carbon and iron" This implies that& the steel die cast parts hae both properties o! iron and carbon" Again& it is also worth noting that this alloy may contain other elements that enhance its per!ormance" $t is important to note that there is clear di!!erence between steel and either cast or wrought iron" This is mainly based on the amount o! carbon content in these materials" $n most cases& the percentage o! carbon in steel may be between >"+O and +"*6O" teel may also contain other elements such as anadium& chromium& tungsten and chromium& 5ust to mention a !ew" All these alloying elements are mainly used to alter the mechanical properties o! steel"
Characteristicsproperties o die cast stee$ We need to note that the physical and chemical properties o! steel depend on the percentage o! the constituent elements" Again& the properties o! steel are slightly di!!erent !rom that o! iron and carbon" What are some o! the desirable properties o! steel? High strength: steel is stronger than most metals that are used in engineering applications" This strength is determined by the carbon content in the alloy" A die cast steel part with higher carbon content will be both harder and stronger" esistance to corrosion: the stainless steel is corrosion resistant thus& ma#ing it a per!ect choice !or a number o! industrial applications" This include mining and chemical processing industries" That is& it doesn0t corrode easily when it is sub5ected to any aderse enironmental conditions" Lightweight : it has a relatiely lightweight than a number o! building materials" 1oweer& the die cast aluminum parts are lighter than die cast steel parts"
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3imensional stability: the steel cast parts do not change with time een when sub5ected to e'treme enironmental conditions" That is& een when sub5ected to high or low temperature& it will in the long run retain its original dimensions" Thermal and electrical conductivity: steel has !ree electrons thus& it conducts both heat and electricity" This is the main reason why steel parts can be used in boilers and other electrical components@sections" ecyclability: steel can be recycled e!!ectiely" This reduces the amount o! scrap metal in the enironment" Again& it cuts the production costs ma#ing the die cast parts cheaper"
$t is quite clear that steel is a ersatile material that can be used !or a wide range o! applications" This is the same scenario when we discussed 3inc& brass and 3inc" .or e'ample& steel can be used to ma#e the !ollowing components *" The scienti!ic or medical equipment: these include scalpel& needles& instrument coers& etc" +" 7arts o! arious in!rastructure such as bridges& railway lines& roads& stadiums& buildings& etc" These may include bolts& connectors& etc" -" Automotie parts and components" %asically& all industries depend on steel" $n short& there are ery many applications o! steel die cast parts@components" Again& this will also depend on the type o! steel in question" 2ay be we should loo# at the types o! steel
Types o stee$ used in die casting There are ery many types o! steel that can be die cast" The American $ron V teel $nstitute has classi!ied all the aailable steel based on their chemical composition as The alloy steels: these steels contain the alloying elements in arying proportions" These alloying elements include nic#el& copper& aluminum& chromium& copper and titanium" These elements impart di!!erent properties on the alloy such as strength& corrosion resistance& strength and ability to be die cast" The tool steels: they are mainly #nown !or their high strength" They contain anadium& cobalt& tungsten and molybdenum in di!!erent quantities" The carbon steel : the die casting companies can choose !rom the low carbon (less than >"-O carbon)& medium (>"- to >"JO carbon) and high carbon steel (more than >"JO carbon)" %asically& this classi!ication is based on the carbon content in the alloy" The stainless steel : they contain between *>O and +>O" This ma#es it corrosion resistant" There are - types o! stainless steel
*" Austenitic stainless steel: contain about *=O chromium& >"=O carbon and =O nic#el" $t is one o! the most common and it is mainly used to die cast plumbing systems& #itchen equipment& etc" 1)
+" .erritic stainless steel: contain between *+ and *O chromium and less than >"*O carbon" The die cast stainless steel can be strengthened by cold wor#ing" -" 2artensitic stainless steel: it contains about *"+O carbon and between ** and *O carbon" The die cast parts can be treated by heat and are magnetic" Bood e'amples are surgical and dental equipment" Again& it is also quite clear that by arying the di!!erent constituents o! steel& we can achiee di!!erent properties" $t is also worth noting that the choice o! a gien type o! steel will be based on the physical properties o! the type is stainless steel" $n summary& in this die casting material section& you need to ta#e note o! the !ollowing *" +" -" 6"
Eou should be able to distinguish between 3inc& brass& aluminum and steel cast parts" Di!!erentiate the metals based on their unique properties List all the types o! alloys !or each metals %e able to choose the right metal wheneer you0re planning to die cast any metal"
Chapter 3: Types Die Casting $n this section& we shall discuss the arious types o! die casting technologies used in industries" We shall !ocus on three main types o! technologies pressure die casting& graity die casting and acuum die casting" We shall discuss the important procedures inoled in these techniques& bene!its and disadantages o! eery process" This is an important section that will guide you wheneer you want to opt !or a speci!ic process to die cast a gien types o! metal %y the end o! this chapter& you should be able to *" Distinguish each type o! die casting technology +" /'plain how each technology wor#s -" List the adantages and disadantages o! each technology
ressure die casting The pressure die casting is suitable !or high olume run parts" This manu!acturing technique can produce parts with thinner wall thic#ness without compromising their quality" $t uses di!!erent types o! die casting machines that may range between => ton and **>> ton" This depends on the ultimate pressure one wishes to achiee" ! course& it will also depen d on the type o! metal die casting technique" Why is it called pressure die casting?
This name basically re!ers to the nature o! the process itsel!" This process does not depend on the !orce o! graity to distribute the molten metal within the mold" $nstead& an e'ternal pressure must be e'erted (air pressure)" This !orce distributes the molten metal within the mold" This implies that& this process is !aster and it can be used to manu!acture high quality parts" This process can be categori3ed as *" 1igh pressure die casting 1+
+" Low pressure die casting The aboe classi!ication depends upon the amount o! pressure used in the process" Again& it is worth noting that high pressure die casting has a wide range o! applications" That is& almost 4>O o! light alloys are manu!actured ia this technique" n the other hand& the application o! low pressure applications constitute about ->O" $n the recent past& companies hae begun incorporating the low pressure die casting process" Advantages of pressure die casting
There are seeral reasons why manu!actures pre!er it to other die casting techniques" These include *" $t can produce parts with superior mechanical properties" That is& the parts hae a good !inish and tight dimensional tolerance@accuracy" This ma#es it a per!ect choice !or producing intricate machine parts" Again& it is the main reason !or its popularity" +" $t is suitable !or large scale production o! parts" This is because the pressure increases rate o! !low o! molten metal" 1oweer& it may not be suitable !or short run p roduction" This is due to high setup costs o! the system" -" The !inal product is in its 8purest !orm9" That is& the !inal product is !ree !rom o'idation e!!ects with no gas trapped within the metals" 6" The pressure casting is relatiely economical compared to other casting techniques" This is !or large scale part production" $n !act& thousands o! parts can be produced be!ore considering a replacement o! the machine components" 4" $t is easier to control the dimensions o! the !inal product depending on the amount o! pressure" J" $t is a per!ect choice !or casting metals with thin walls and lightweight" Disadvantages of pressure die casting
This metal part manu!acturing process is associated with the !ollowing main disadantages *" The entire process is only suitable !or large scale metal part production" +" The initial set up costs is relatiely high" This is due to the technology inoled" -" The process is mainly suitable !or high;!luidity metal parts" $n short& this is an oerall oeriew o! pressure die casting" o& we need to discuss the arious types o! metal die casting technology"
5igh pressure die casting techno$ogy The high pressure die casting is one o! the most competitie metal processing technologies used in the manu!acturing industries today" At times& it may be re!erred to as the pressure die casting" $n this metal die casting process& the molten metal is in5ected in a metal die under high pressure" Normally& the process ta#es place under high speed and pressure" $n most cases& the die casting temperature is always around >>RC during the casting process"
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This technology has been adopted by a number o! manu!acturing companies" This is due to the superior and thin walled die cast parts" &dvantages of high pressure die casting process This manu!acturing technique guarantees the !ollowing desirable properties
*" $t is suitable high olume production o! parts" +" $t is possible to achiee parts with ery tight tolerances" -" The die cast parts hae superior !inish i"e" they hae a smooth sur!ace with !ine grain !inish" 6" $t guarantee high metal part production rate" 4" The process is also suitable !or parts with ery small thic#ness i"e" about * to +"4 mm J" This is a precise manu!acturing process& thus& little or no additional machining may be required" "
*" +" -" 6"
The tooling costs is higher than the graity die casting processes" $t may not be economical !or small scale part production process" This process requires comple' machinery" The si3e o! casting is limited by the machine si3e"
Again& it also worth noting that this process may be prone to porosity problems" This is the main reason why the eacuation chamber technique may be used to reduce its e!!ects"
6actors to consider in pressure die casting This is a !undamental aspect that will guarantee the success o! the entire process" That is& the choice o! a recommended pressure& heating temperature and weight are #ey issues to consider" This choice o! a suitable metal is also an integral aspect" Not !orgetting the e!!iciency o! the pressure die casting machine" .or instance& an e!!icient machine will guarantee high production rates I about +>> castings per hour" This will depend on the comple'ity o! the part and the capacity o! the die casting machine" This ma#es sustainability and suitability some o! the !undamental aspects to consider" $n most cases& this die casting process is mainly used to cast 3inc and aluminum" These are a number o! !actors that ma#es them suitable !or this process and these include their aailability and the !act that they can be recycled" The two metals can be recycled without losing their essential priorities" Let0s e'amine the requirements !or each case
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3ie casting zinc: the molted 3inc is in5ected at 6+4RC" Normally& the speci!ic pressure is maintained at about 4>> bar" This requires a high grade mold and high speed" 3ie casting aluminum: the molten aluminum is maintained at J>RC" This requires a high grade mold and the process should ta#e place at a high speed with the temperature maintained at *>>> bar"
$n summary& by considering all the aspects mentioned aboe& you can decide whether this process is suitable !or a gien application or not" Low pressure die casting This is yet& another die casting technique that is popular in ery many industries" The sur!ace !inish o! this process can be compared to that o! the graity die casting technology" Thou& they are not actually the same" $n this process& the molten metal is in5ected in the mold under low pressure" Benerally& the die cast parts produced by the low pressure die casting are better than the graity die casting" Again& it is important to note that they are not as g ood as those produced by the high pressure die casting" The technique is mainly used to die cast the low melting point alloys such as those o! magnesium and aluminum" $n most cases& the pressure required to sustain the process may range between + and *4 psi" This pressure causes the molten metal in the !urnace to rise up a tube and enter a die caity" The air pressure is only released a!ter the molten metal changes into solid" &dvantages of low pressure die casting This process has the !ollowing #ey bene!its
*" +" -" 6" 4" J"
$t is suitable !or small production quantities" $t has a !airly high metal part production rate Buarantees high yields I about >O The casting can be heat treated The production costs is slightly lower than the high pressure die casting" $mproed sur!ace !inish thus& reduced !inishing operation" The sur!aces produced through high pressure die casting are better" " An improed linear tolerance than graity casting" =" $t0s possible to obtain parts with thin walls" 3isadvantages of low pressure die casting This manu!acturing technique has the !ollowing main disadantages
*" The tooling costs is slightly higher than other casting technologies such as graity casting" +" $t requires comple' machinery that may be ery e'pensie"
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$n summary& the high pressure and low pressure die casting technologies share a lot manu!acturing process" The mainly di!!erence comes in the amount o! p ressure required" ! course& this is the only integral !actor that may ma#e the tools used to ary slightly" $t is important that you understand the main !eatures you0d wish the !inal product to possess" This could be a superior sur!ace !inish or one with a tight tolerance" .rom this you can decide to go !or a low or high pressure die casting process"
The 7ra/ity die casting The graity die casting is one o! those processes that is popularly used !or both medium and high olume production process" ,nder normal circumstances& this process uses permanent mould& thus& it is easier to achiee a near net shape product" This die casting capability aries !rom one manu!acturer to the other" That is& there are those companies that use the automated systems whereas other use the manual systems" Again& the weight o! the !inal product that can be cast depend on the type o! machine" The graity die casting technique has been adopted by most companies due to the !act that it reduces the production cost" The tooling that is used in here& is cheaper that those used in the high pressure die casting" A company that has all the aboe manu!acturing techniques can always e'amine the pro5ect at hand and subsequently choose a technique that suits their customers" What does the process involve?
,nli#e the high pressure die casting where the molten metal moes into the die due to high pressure& this die casting technique depends on graity" NT/ There0s no any other !orce that is applied to !acilitate the !low o! molten metal" This metal parts manu!acturing process is suitable !or non;!errous alloys" That is& copper& aluminum and 3inc alloys" $t is a manu!acturing process that is mainly used to produce heaier metals sections" 1oweer& the parts are thinner as compared to those produced by sand casting" This process inoles !our ma5or processes *" The mould should be heated& sprayed with a lubricant and then closed" The lubricant helps to control the temperature o! the mould" +" The molten metal is poured in the mould and allowed to cool" -" The die is opened to remoe the metal cast components" This can be done with the help o! e5ector pins" 6" The die is prepared !or the ne't casting process"
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The graity die casting can be used to manu!acture components with comple' shapes" /'amples o! products that can be manu!actured using this technique include diesel engine parts& air conditioning systems& cylinder parts and ale !low systems& 5ust to mention a !ew" &dvantages of gravity die casting The main adantages o! this manu!acturing technique include the !ollowing
*" %etter dimensional accuracy" +" Thinner wall can be cast thou& they can be smaller than those o! the pressure casting process" -" $t reduces a number o! secondary operations" 6" $t imparts desirable mechanical properties on the metal parts e"g" high tensile strength" 4" The !inal parts hae smoother sur!ace than those made !rom sand casting" J" A !aster production can be reali3ed" " $t0s possible to produce undercuts with the help o! undercuts" 3isadvantages of gravity die casting The process has the !ollowing #ey disadantages
*" $t has high initial cost" +"
The Vacuu# die casting The acuum die casting technology has been adopted by companies that manu!acture large parts" Normally& these are parts that tend to hae porosity problems" This is due to the air entrapped within the casted component" er the years& the acuum die casting has proed to be the best way to eliminate the porosity problem" How does the vacuum die casting work?
$n most cases& the die is manu!actured !rom steel in an airtight bell housing" $t has two receiers I outlet top and sprue through which the molten metal enters the die and the acuum" The molten metal !lows into the die due to pressure di!!erence" The molten metal !lows up the sprue to the die where the metal solidi!ies" This cycle #eeps on repeating itsel!" $n the acuum die casting& the 24
desired pressure di!!erential is controlled by arying the acuum" This is between the molten metal and caity" The process requires a tight control system that can be achieed during the design process" The acuum die casting has been adopted in a number o! manu!acturing companies" The automotie industries depend on this technique to produce arious engine parts" The advantages of vacuum die casting The main bene!its o! this manu!acturing technique include the !ollowing
*" +" -" 6" 4"
The die cast parts hae good welding properties" The parts possess high mechanical strength" They are associated with low production scatter" $t is superior when it comes to reducing gas porosity" The die produces accurate parts that may not require secondary operations"
The disadvantages of vacuum die casting This metal casting technique has the !ollowing main disadantages
*" The initial setup cost is relatiely high" +" $t is cumbersome to setup a acuum die casting process" -" ome parts may requires secondary operations" They may not be as precise as those produced by pressure die casting" How to make vacuum die casting successful
To get the desired shapes& it is important to obsere the !ollowing #ey aspects *" .or high per!ormance& the acuum component must be o! high quality" %oth the shot assembly and die must be sealed tightly" This will guarantee e!!iciency and reliability" +" To attain high reproducibility and precision& it is important to control both the pressure and elocity pro!iles" -" The !ollowing components should be controlled die spraying& plunger lubrication& molten metal !ees and die temperate control" NT/ Achieing an optimi3ed acuum casting process can be a challenging process" $t0s only a high acuum that can !ul!ill the requirements o! the aboe speci!ication" There!ore& each process should be optimi3ed" Benerally& this process can be used to manu!acture pressure tight components" The parts are used in the automotie& aerospace& gas manu!acturing and !ood processing industries among other industries" ome o! the most common parts manu!actured ia this technique include oil pumps& engine cradles& bra#e components& transmission trans!er cases& mani!olds and oil !ilter mountings& amongst others" $n summary& this is a unique manu!acturing process that plays a signi!icant role in the manu!acturing process" $n this chapter& we should be able to note the !ollowing #ey points 2
*" List and e'plain the di!!erent types o! die casting technologies" That is& pressure die casting& graity die casting and the acuum casting" +" /'plain the di!!erent adantage and disadantages o! each manu!acturing process" -" elect the best die casting technique !or a particular pro5ect" 6" /'plain the principles o! operation !or each manu!acturing technique
Chapter 4: Die Casting *achine Choosing the right die casting machine is an important process" ince these machines were inented& they hae undergone a number o! innoations" All these aim at improing *" The process !le'ibility: the machine allow !or di!!erent metal die casting procedures" That is& whether it is lean& compact or e'tended die casting process" +" A high degree o! reproducibility and precision: the modern die casting machines allow !or a precisely controlled and dynamic casting process" This guarantees consistency in the parts produced" -" /nergy saing: this ensures total cost adantage" This is achiee through a good control o! the machine" 6" ne;stop die casting solution: this allows !or easy handling thus& an improed per!ormance o! the machine" All these machines ary in both design& speci!ication and per!ormance" Ta#e !or instance& those casting machines manu!actured by L"" 2achinery& $nc" and The Toshiba DC; eries" /ach machine has unique speci!ications that ma#e them suitable !or a speci!ic tas#" %elow is an e'ample o! a die casting machine manu!actured by The Toshiba 2achine apan" Considerations when buying die casting machines There is one simple rule& the machine should be able to per!orm the desired tas#" That is in terms o! ma'imum productiity and e!!iciency" The critical parts to consider in a machine include the !ollowing The ton capacity: they come in di!!erent capabilities that may range !rom =>& *+> to +4> tons" This will depend on the tas# the machine should per!orm" The machine base: this is the section where the entire machine structure rests" $t should hae a strong structural base to support the machine" The die loc1ing mechanism: most machines use the hydraulic systems" $t should be ad5ustable with the ability to hold all types o! dies" The heat exchanger system: it is mainly used to cool the system" This preents oer heating o! the mould" "n4ection and e4ection system: the in5ection system operates based on a hydraulic system" They are designed to be powered by high pressure accumulator"
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The hydraulic system: it is responsible !or all the moements o! arious components" $t con sist o! the !ollowing #ey parts& relie! ale& accumulator& ane pump& unloading ale and ane pump" These may ary depending on the design o! the die casting machine" The electrical systems: these essential parts o! the hydraulic machines" The electrical parts may consist o! relays& contactors& switchgears& motors& etc"
$t is important that you ealuate eery section o! the machine at the time o! purchase" $t should be one that meets the per!ormance criteria o! your client0s needs" Now that we hae an idea o! why we need these machines and the basic sections that ma#e up the machine& we may discuss the arious types o! metal die casting machines !or di!!erent applications"
The pressure die casting #achines The pressure die casting is a common process across ery many industries" There are a number o! companies that manu!acture the pressure die casting machines" They come in di!!erent con!igurations depending on the metal to be die cast" .or instance& there are the !ully automated and semi;automated machines" There are two main types o! pressure die casting machines and they include *" The hot chamber pressure die casting machines: these machines are also aailable in di!!erent con!igurations and designs" They hae di!!erent loc#ing !orces depending on the design o! the machine" These machines are designed !or high productiity and accuracy" The machines are mainly used to die cast magnesium& 3inc and lead alloys" These are basically metal alloys with low melting point" To ensure high leel o! accuracy& the modern machines are equipped with a complete control system" That is& a closed;loop control system" They are designed to reduce production costs by being energy e!!icient" +" The cold chamber die casting machines: they come in di!!erent capacities that may ary !rom =>& *=>& +=> to 6>> tons" These machines hae been designed !or metal alloys with high melting point such as aluminum& brass and copper" They are designed to guarantee high leel o! accuracy and repeatability" This ma#es them suitable !or high scale production" There are both the ertical and hori3ontal machines aailable" $t depends on the manu!acturing requirements" The hori3ontal hot chamber and cold chamber die casting machines are some o! the most common machines that used in this industry" $n short& the choice o! a cold or a hot chamber die casting machine will depend on the type o! metal you0d wish to die cast" That is& whether it is an alloy with high or low melting point"
The gra/ity die casting #achine The graity die casting machines are also used in the metal die casting industry" They are aailable in di!!erent con!igurations& depending on the type o! metal to die cast" The modern die casting machines !eature adanced technology that aim to increase production and quality o! the 2(
!inal die cast components" They include manual& automate and the 7LC controlled systems" The aailable graity casting machines can be used to cast a wide range o! metal such as copper& aluminum& 3inc& iron and copper alloys" %roadly& the aailable machines can be classi!ied as ertical& inclined or hori3ontal" 2ost o! these machines hae hydraulic systems that can be used to ad5ust the degree o! tilt" That is& the title angle can ary between > and > degrees" The tilt may be ad5usted depending die casting process" The end users can choose !rom the !ollowing options The tiltable machines: these machines are mainly used to achiee better !inishes" They can be ad5usted depending on the type o! metal" They are mainly used to die cast copper& 3inc and aluminum alloys" With this machine& it is possible to achiee better dimensional accuracy and most o! them are basically high capacity machines" The hydraulic die casting machines: these machines are mainly used to die cast copper and aluminum alloys" They come in both the tilt and non;tilt con!igurations" The non%tiltable machines: these machines are mainly used to die cast non;!errous metal such as aluminum& 3inc and copper" They hae both the digital and hand operated !unctionalities"
$n summary& these are the most common types o! die casting machines aailable in the mar#et" $t is import to consider !unctionality& conenience and quality o! the !inal product be!ore opting to purchase one" As a general rule& you need to acquire these machines !rom an authori3ed dear"
Die casting #o$d The die casting mold is an important tool in the metal casting industries" The mold hae channels& which the molten metal !lows to !orm the desired shape and design" The design o! the mold will depend on the desired shape o! the !inal product" $n the metal die casting& the mold design is a !undamental aspect o! the entire manu!acturing process" This is !rom the !act that& all attributes and shape o! the die will a!!ect the !inal product" Normally& the manner in which the molten metal !lows will depend on the die casting technique" That is& !or high pressure die casting& the molten metal will !low due to high e'ternal pressure" .or graity die casting& the !low will be due to the !orce o! graity" An image o! a die casting moldX What determines a quality die casting mold? This will be determined by a number o! mold design !actors" They must meet the desired design speci!ications" The #ey die casting mold parts to consider include The die draft : this re!ers to the e'tent a mold core is tapered" This reduces chances o! shrin#age and ma#es it easy to remoe the cast part" .actors that determine the type o! dra!t include type o! metal alloy& wall thic#ness and the shape o! the die"
2)
The parting line: this is the line that connect arious sections o! the mold" $t should not de!orm due to any wor# strain to aoid any non;uni!ormity molding" The fillets: these are smooth sur!aces that !orm concae 5unctions" They are inserted on the sharp corners o! the mold" %asically& they create round edges ma#ing it easy to re moe the die cast part" NT/ They are not placed on the parting lines" The bosses: they are used as mounting points during the mold design" To !ill the deep bosses& ribbing and !illeting may be necessary" $t helps to achiee a uni!orm thic#ness o! the mold" The ribs: these structures are used to improe the strength o! the material& reduce stress crac#ing& and improe !ill capabilities" The holes and windows: ma#es it easier to e5ect the die cast part since it creates substantial dra!ts" The unwanted casting can be eliminated with the help o! this structure" The symbols: these could include brand names& logos or instructions" They can be included during the mold design" $t is worth noting that their use can only increase production costs" This depends on the comple'ity o! the design@symbol"
$n summary& designing the die casting mold can be a challenging process" $t requires both the metal casting company and consumer to wor# ery closely together" This should be !rom the design conceptuali3ation& product prototyping to the actual design process" %y the end o! this chapter& you need to hae an understanding o! the arious machines used in the metal die casting" This is essential !or the manu!acturing companies in this industry" $t0s only by choosing the required die casting machine that you can reali3e a good end product"
Chapter : Die Casting rocess To ma'imi3e on pro!itability& reliability and per!ormance o! the metal die cast parts& it is important to adopt the best manu!acturing process" The manu!acturing process will depend on seeral !actors that we hae listed in the preious chapters" The main aspects include *" The type o! alloy: high or low melting point alloy" +" The desired !inish" This can be ery !ine or one that may require secondary !inishing operations" -" i3e o! the die cast part and application" We hae already discussed some critical aspects o! the die casting processes" These include *" +" -" 6"
Where each process may be used and reasons why" The choice o! die casting machine !or each process" The basic application o! each process" The adantages and disadantages o! each process"
$n this chapter& we shall !ocus on the step;by;step process inoled in each case" The main metal die casting process that we shall !ocus on include 2+
ressure die casting process $n pressure die casting& the molten metal is sub5ected to high compression rates and speci!ic pressure" $n other words& the process ta#es place at both high pressure and speed" $t is used to cast non;!errous alloys" Depending on the type o! alloy& the casting process may done in the !ollowing chambers *" The cold die casting chamber +" The hot die casting chamber The quality o! the die cast part may depend on a number o! engineering actors such entilation systems& design o! the die& eacuation process& pressure and temperature stability among other aspects" An image o! the processX Benerally the high pressure die casting process is used !or high productiity manu!acturing process" That is& where high precision& sur!ace clarity and dimensions stability is required" Bood e'amples are parts with ery thin thic#ness" $t is one o! those processes that has been adopted !or high olume run parts" The machines also ary in tonnage depending on the speci!ied criteria" That is& they may ary between => and **>> tons" thers hae high capacity"
7ra/ity die casting process This metal die casting technique depends on the !orce o! graity" That is& the molten metal is allowed to !low without an e'ternal !orce or pressure" The nature o! the !inal product will depend on the design o! the graity die casting machine" The graity die casting technique is mainly used to cast light alloys" %e!ore the process begins& the mold must be heated and sprayed with a lubricant" The molten metal is poured in the die and allowed to !low with the help o! graitational !orce" The metal alloy then cool and the die cast part remoed" Normally& the coating is used due to the !ollowing #ey reasons *" 7reent premature solidi!ication" The molten metal !lows at a low rate since it depends on !orce o! graity" There are graity die casting machines that are titled to !acilitate !low" +" $t preents the molten metal !rom adhering o! the wall o! the mold" Benerally& these are some o! the simplest techniques used to process metals" The principle o! operation is almost the same e'cept !or the manu!acturing procedure inoled" The choice o! a particular manu!acturing process should be based on those listed on the preious chapters"
Chapter %: Die casting app$ications 2etal die casting has become popular in ery many industries across the globe" These include automotie& recreational& medical& alternatie energy& electrical and transportation& 5ust to mention a !ew" This is due to its !le'ibility and reliability" $t0s possible to attain di!!erent sur!ace !inishing requirements" These include comple' shapes& near;net shape& ery tight tolerances and high strength" 3-
0pp$ications o &rass die casting The brass die cast parts are used in application that require e'treme operational characteristics" The high pressure die casting produces parts that are *" +" -" 6" 4" J"
1ae relatiely high strength" Corrosion resistance" 1eat resistance" Keasonable electrical conductiity" 7ressure tight (up to ->> psi)" /asy to polish"
$deally& this materials can be used in ery many industries such as aerospace& automotie& chemical processing& alternatie and decoratie industry& 5ust to mention a !ew" The brass application imagesX
0pp$ications o a$u#inu# die casting This is a common alloy used to die cast products" 1oweer& it is prone to crac#ing shrin#ing and crac#ing at eleated temperature" $t can be alloyed with silicon or copper" This improes its hardness and !luidity" $t is dimensionally stable ma#ing it a per!ect choice !or comple' and thin walled shapes" Due to its low melting point& it is a per!ect choice !or hot chamber die casting" The aluminum applicationsX
0pp$ications o 'inc die casting These alloys are easy to die cast" They can be mi'ed with other metal alloys to improe the chemical and physical properties" Minc has a low melting point& this ma#es it suitable !or hot chamber die casting" $t used to die cast parts that should be sturdy& but with high precision" ome o! these !actors hae been discussed in the preious chapters too" These die cast parts are used in the manu!acturing and processing industries" ome o! these parts include $nsert image o! gearsX
0pp$ications o stee$ die casting The steel die casting is popular in ery many industrial applications" That is& automotie& manu!acturing& production& energy production alternatie energy& etc" .urthermore& they are used to ma#e the metal die casting tools" This is due to the superior physical and chemical properties" The stainless steel is used to die cast medical equipment and instruments parts" $t doesn0t rust thus& the components can guarantee optima per!ormance" $nsert image !or steel die casting applicationX
0pp$ications o copper a$$oys Copper alloys are mainly used to die cast mechanical parts" uch alloys are #nown to be durable and high resistance alloys" A reason why they are used in electrical and plumbing applications" The copper die cast parts used in applications that should hae 31
*" +" -" 6" 4"
uperior resistance to corrosion" 1igh electrical and thermal conductiity" uperior bearing;sur!ace qualities" 1igh elongation and high tensile strength" Low to medium hardness"
This ma#es copper to be a ersatile alloy in the metal die casting alloys" The parts are used in electrical& chemical manu!acturing and petroleum industries& 5ust to mention a !ew" $nsert images o! copper die cast partsX $n summary& the choice o! a speci!ic metal will depend on the desired application" This calls !or one to understand the intrinsic chemical and physical properties" 2ost o! these hae been discussed in the preious chapters" $n general& the die casting has ery many application in industrial and domestic applications" $t is important that one chooses the right metal and manu!acturing technique"
Chapter (: The 0d/antages Die Casting .rom the preious chapters& it is quite clear that die casting is a ersatile process used in industries" $t is possible to produce comple' and dimensionally accurate parts" This depends on *" The right die casting technique" +" The metal alloy to use" %y integrating the two& you0ll get a die cast component that will be suitable !or any application" The adantages o! die casting outweigh its disadantages" A reason why it has been adopted in the industry" Let0s hae a loo# at the main adantages o! this process Economical manufacturing process: the process o!!er one o! the best total cost adantages" $t
requires that one adopts a desired die casting process" This could be high pressure& acuum or graity die casting" /ach process is designed to proide cost bene!its" This depends on the manu!acturing process" .or e'ample *" The high pressure die casting is used !or ery thin and accurate parts" +" The graity die casting can be used !or parts that may require additional secondary operations" There are a number o! metal die casting designed !or di!!erent manu!acturing requirements" This may include long or short run production serices" 1oweer& this will only be possible by hiring a reliable and a trustworthy company" That is& one that can choose a process depending on the process requirement" The parts are generally durable" This implies that they hae a long cost term bene!its" The die cast parts hae a long serice li!e" This ma#es them a per!ect choice !or nearly all app lications" 32
Rapid or high speed production process: with die casting& as long the right metal alloy and
manu!acturing process has been chosen: the !inal product can be reali3ed within a short period o! time" This is the main reason why it is highly recommended !or high olume production" The tooling process is simple as one mold@die can be used to produce di!!erent parts o! the same speci!ication" Again& depending on the desired sur!ace !inish& an appropriate technique can be chosen" Thus& the !inishing operations can be minimal i! not eliminated completely" $deally& thousands o! parts can be produced without necessarily using an additional tooling" $t doesn0t matter whether they are comple' shapes or those with higher tolerances" This reduces the lead time signi!icantly" High precision, accuracy and dimensional stability: this is a crucial part in the manu!acturing
industry" $t0s only through die casting that you can get an accurate and precise part" The parts are dimensionally stable and it is easy to maintain tight tolerances" They are also heat resistant due to the manu!acturing process that inoles heating the metal" As long as the tooling is designed to the required speci!ications& the !inal product will de!initely meet the desired design requ irements" This will also depend on the desired manu!actured process" %e it graity or pressure die casting" The metal die casting technique is used !or parts that require tight dimensional tolerance" The strength and weight : when compared to other metal manu!acturing processes such as
in5ection molding& die casting produces stronger parts" This does not compromise both weight and dimensions" With pressure die casting& it is possible to obtain parts with walls& lightweight and stronger" This ensures that the part maintains its quality and desired !eatures" 2ost die cast parts are compact and they may not require other 5oining processes" uch parts are stronger" ince di!!erent metal die casting techniques can be adopted !or speci!ic alloys& the required strength and weight can be reali3ed easily" Different finishing techniues: this ma#es the process ersatile and compatible with a number
o! manu!acturing process" $t doesn0t matter whether one requires a te'tured and smooth sur!ace" $t all requires one to choose the best manu!acturing technique" That is& high pressure die casting !or ery !ine !inish or graity casting !or sur!aces that require minimal secondary operations" Again& unli#e other manu!acturing processes& these !inishing operations are chea p" This is because they require minimal sur!ace preparation" !imple assembly process: the metal die casting has a simple assembly process that is not as
complicated as in other metal manu!acturing processes" The process proide integral !astening elements that may include studs and bosses" This doesn0t imply that this process *>>O per!ect" ome procedures may b e e'pensie !or short run production processes" This requires that the company o! choice should be able to adopt the 33
right manu!acturing process" $t is only through this that one can bene!it !rom the adantages listed aboe" The company should proe beyond any reasonable doubt that manu!acturing a gien part will be economical when the die casting process is adopted" therwise& it will be wise to consider other manu!acturing processes" As we had mentioned earlier& the metal die casting may hae some disadantages" This is actually the main reason why the process can0t be adopted !or all manu!acturing processes" $n the ne't chapter& we shall loo# at some o! these drawbac#s"
Chapter ): Die Casting Deects ,nder normal circumstances& the metal part manu!acturers use di!!erent processing techniques to get the desired designs" That is& one process may be per!ect !or short run products thou& it may be ery e'pensie !or long run production process" This calls !or a critical ealuation o! eery process be!ore it is adopted !or a speci!ic tas#" As a matter o! !act& each metal die casting process has its unique adantages and disadantages that we0e discussed in the preious chapters" %elow is a summary o! the disadantages o! die casting process High initial cost : setting up the metal die casting plant can be an e'pensie process" This is the main reason why it is highly recommended !or the metal die casting companies to conduct a comprehensie !easibility study" $t is through this that they can tell whether the process is !easible or not" The cost o! the dies& machines and other equipment is somehow high" Limited to high production: this process is only economical !or large production" The small scale production ma#es the process ery e'pensie" This e'plains the reason why most companies aoid small quantity production" The process is limited to fluidity metals : this re!ers to those metal alloys that can !low" $t will be nearly impossible to !orce a metal that can0t !low through the d ie" There!ore& it is important to ealuate all !actors that can a!!ect the !luidity o! the metals" The compan y should hae a lab to test each metal to ensure that they meet the desired die casting criteria" Limitation of the type of metals to die cast : not all metal alloys can be die cast" $n most cases& the process is suitable !or non;!errous alloys"
Apart !rom this& it is also worth noting that the process may not be suitable !or heay casting" This is the main reason why companies opt !or the sand casting processes" Thus& you need to be sure o! the e'act speci!ications o! the metal to die cast" Again& you need to ta#e special considerations when remoing the cast part !rom the die" This is to aoid porosity problems"
34
.rom the aboe& it is quite eident that the adantages o! die casting process are actually more than the disadantages" This !urther con!irms the reason why it has been adopted !or a number o! manu!acturing processes" Eou need to hae e!!ectie measures that will eliminate any circumstance that may compromise the quality o! the !inal die cast component"
Chapter +: Die Casting 0ssociation Li#e other pro!essions& the die casting association is an umbrella o! people and companies in the die casting industry or business" These associations not only oersee the how these companies go about their businesses& but also set rules and guidelines that they should !ollow" The associations also proide aenues !or acquiring new in!ormation and news" These may include research wor# or news articles" /'amples o! die casting associations include The North America Die Casting Association (NADCA) $t was !ounded in *== a!ter the ociety o! Die Casting /ngineers (DC/) and American Die Casting $nstitute (ADC$) merged" The ADC$ was !ounded in *+=& while DC/ was !ounded in *4" NADCA !ocuses on promoting awareness and growth in the die casting industry" $t reaches out to its members through maga3ines and newsletters" This die casting association !ocuses on deelopment V research& mar#eting& education& design assistance& goernment a!!airs and chapters relations among other !actors that a!!ect this industry" The Canadian Die Casters Association This a die casting association whose membership are companies and die casters in Canada" $t communicates important in!ormation to its members" $t also represents the interest o! its members to both the goernment and other sta#eholders" This association plays the !ollowing #ey roles *" Aail all material that aim to promote the industry entures" +" Collect and distribute important in!ormation o! interest to its members" -" 7romote industry standards" 7roide a !orum !or e'change o! in!ormation" The Die Casting ociety This society was !ormed in *J" $t was to represent the iews o! all die casting companies" $t promotes technology and a !orum !or debate and discussion" $n addition to this& it also proides aluable in!ormation that aim to educate its members" $t is important to note that there are ery many die casting association across the globe" $n !act& almost eery country has their own die casting association" 1ere is a list o! other die casting associations"
3
,u##ary 2etal die casting is an important manu!acturing process that is used in ery many industries" This is due to the numerous bene!its listed in this e%oo#" $deally& this e%oo# has been designed to proide a complete guide to any die casting application" That is& understanding what metal casting is& types o! casting processes& machines used and the processes inoled" $t also e'pounds on the arious properties o! arious alloys" Thus& ma#ing decision should not be based on one parameter" $t is important that one blends all these elements to reali3e e!!iciency and ma'imi3e on production"
