The Manufacture of Aluminium Alloy Wheels
Contents
Introduction Charcterstics Production Methods General Types Of Alumunium Wheels Production steps Production Flow Advantages References
Aluminium Alloy Wheels * An alloy of Aluminium or magnesium * For the production of aluminium alloy wheel Al-Si casting alloys are mostly used as a raw material * Main alloying Elements are silicon,Magnesium,iron,manganese and zinc
Characterstics
Lighter Wheels Can Improve handling by reducing Unsprungmass Alloy Wheels are Lighter than their steel equivalents Alloy Wheels are prone to galvanic corrosion Good Life ,low ductility and quite brittle Good Strength and they are typically lighter for the same strength and provide better heat conduction.
Production Methods
Forging : Forging can be done by a one or multistep process forging from various magnesium alloys, Wheels produced by this method are usually of higher toughness and ductility than aluminum wheels, although the costs are much higher.
Low pressure casting (LPDC) This process usually employs a steel die, it is arranged above the crucible filled with molten magnesium. Most commonly the crucible is sealed against the die and pressurized air/cover gas mix is used to force the molten metal up a straw like filler tube into the die. When processed using best practice methods LPDC wheels can offer improvements in ductility over HPDC magnesium wheels and any cast aluminum wheels, they remain less ductile than forged magnesium.
High pressure die casting
This process uses a die arranged in a large machine that has high closing force to clamp the die closed. The molten magnesium is poured into a filler tube called a shot sleeve. A piston pushes the metal into the die with high speed and pressure, the magnesium solidifies and the die is opened and the wheel is released.
General Types of Al Alloy Wheels
1.Forged Al Alloy Wheels
2. Single piece Al Alloy Wheels
3. Multi piece Al Alloy Wheels
Forged Al Alloy Wheels
Forged Al alloy wheels are generally used in medium and heavy trucks. A forged Al wheel is shown in Figure Forged wheels are manufactured by using one piece of aluminum alloy that gives fuel savings, greater payloads and lower weight.
Single piece Al Alloy Wheels
*Most Al wheels are singlepiece castings manufactured from a variety of casting Processes *The cast product provides an infinite number of styling iterations and optimized for minimum weight and cost *This type of wheels can be used in passenger cars, minivans, sport utility vehicles
Multi piece Al Alloy Wheels
Multi piece wheels are actually manufactured from two or more components that are securely welded together. The process has the unique advantage of having a rolledand-spun wrought aluminum rim combined with a cast disc, made of mold This cast disc can provide lower tooling cost
Production steps
a. Melting of Al Alloy b. Degassing Process c. Low Pressure Die Casting d. Solidification of Al Alloy e. Real Time Radioscopic Inspection
Production Flow
Press 1
Furnace
robot
Press 2
A mix of new alloy and recycled wheel is introduced to the Furnace, and the Robot transfers charges to each Press and unloads each in turn to the Water Bath. The wheels are inspected before Machining and Painting. Water bath
X-ray station
Machining and painting
store
Process Flow in More Detail Store of Raw Materials
Store of Rejected Wheels
Press 1 No
Prepare Materials
Furnace
Robot
Water Bath
X-Ray OK?
Machining and Ye s Painting
No Final Checks OK? Ye s
Store
Press 2 Work Order Received
Close Work Order
Real Time Radioscopic Inspection
Advantages
They provide less fuel consumption. Because density of Al is only 1/3 of the steel. And for 4-aluminum wheels/car, the total weight reduction is 4-8 kg. Consequently, the fuel saving rate is about 7%. Al wheels have better performance than steel wheels. Because of lighterweight, Al wheels gain more quick acceleration and short braking distance. With Al wheels, driving is more comfortable. It means to get excellent impact absorption and more accurate balancing Al wheel utilization maintains effective dissipation of heat. It improves the service life By using Al wheels, there becomes no air leakage. Because of precise and accurate machine usage, there occurs very rare air leakage and excellentsafety. Al alloys wheels have good corrosion resistance. They are suitable for running under very severe weather conditions Al alloy wheels have outstanding appearance. Actually, they have various style and brightly shining surface. They are also very attractive
References
Effects of Upsized Wheels and Tires Tested - Tech Dept. - Auto Reviews". Car and Driver. Retrieved 2011-08-08. Chang C,Modelling for Impact test of Aluminium Wheels,Ph.D.Thesis,Department Of Mechanical Engineering,National Central University,Taiwan Wheelweights.Net". Wheelweights.Net. Retrieved 2011-08-08 Grubisic,V.Fischer, G.Design criteria and durability approval of wheel hubs.Society of Automotive Engineer,Inc.Warrendale,Pennsylvania. Ramamurthy Raju,P.,Satyanarayana,B.,Ramji,K.,Suresh Badu,k.Evaluation of fatigue life of aluminium alloy wheels Zhao,s.,Wang,Z.Fatigue design.Mechanical Industrial Press ,.
