SCIMATP May 31, 2012
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Individual Project Scrapbook
Include the following: 1. Original Paper, signed 2. Improved Drawing of your 2062 gadget 3. Identify the important parts/components of the gadget 4. Identify the material that you think should make up each part 5. Include a discussion of the important properties of each material that makes it suitable for the
Classification of Materials
Classification of Materials • classification of materials is usually based on the atomic bonding forces of the materials. • General Classification – Metals – Ceramics – Polymers – Composites – Semiconductors
ACTIVITY • Identify whether the material given to you is a metal, ceramic, polymer, composite, or semiconductor – You may ask anyone in your group to help you • Paste your material name under the correct heading on the manila paper pasted on the board
METALS
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Ring: 75% copper, 25% nickel Center: 92% copper, 6% aluminum, 2% nickel
METALS • They have electrons.
large
numbers
of
non-localized/free
• General Properties: 1. shiny luster 2. grayish-silver color (except gold and copper) 3. hardness (except sodium and calcium) 4. good heat and electrical conductivity 5. high melting and boiling points (except mercury) 6. malleability (can be hammered into a sheet) 7. ductility (can be pulled into a wire)
METALS • Examples: • Ferrous metals and alloys (irons, carbon steels, alloy steels, stainless steels, tool and die steels) • Nonferrous metals and • Applications: alloys (aluminum, copper, • coinage, jewelry, magnesium, nickel, automobiles, structural titanium, precious metals, components for refractory metals, buildings, hulls of large superalloys) ships, etc.
CERAMICS
http://www.turkuceramics.fi/kuvat/turku-ceramics_en.jpg
CERAMICS • Ceramics are compounds between metallic and nonmetallic elements. • They are most frequently oxides, nitrides, and carbides and are composed of clay minerals, cement, and glass. • General Properties: 1. typically insulative to the passage of heat and electricity 2. more resistant to high temperatures and harsh environments 3. hard but very brittle
CERAMICS • Examples • Glasses • Glass ceramics • Graphite
• Applications: • insulators, magnets, aerospace, biomedical, construction, nuclear industries
POLYMERS • Many of them are organic compounds that are chemically based on carbon, hydrogen, and other nonmetallic elements. • They have very large molecular structures. • Properties: 1. low density 2. may be extremely flexible 3. Good electrical resistivity
POLYMERS • Examples: • Thermoplastics plastics • Thermoset plastics • Elastomers
• Applications: • plastic bags, electrical and thermal insulation, toys, pipes, flooring, clothing, paints, adhesive
SEMICONDUCTORS • have electrical properties that are intermediate between the electrical conductors and insulators • the electrical characteristics are extremely sensitive to the presence of minute concentrations of impurity atoms • Applications: • integrated circuits • Electronics
COMPOSITES • Composite materials are engineered materials that consist of more than one material type . • They are designed to display a combination of the best characteristics of each of the component materials
COMPOSITES • Example: • Fiberglass – glass fibers are embedded within a polymeric material - acquires strength from the glass and flexibility from the polymer • Applications: • space shuttles, construction of pavement, roads, parking lots, armor
Density
Stiffness
Strength
Resistance to fracture
Electrical Conductivity
Seatwork
ELEMENT
ASSIGNMENT
• Download Atoms, Bonding and Structure v2.0 • Explore and learn
References • Callister, William Jr. (2005) Materials Science and Engineering: An Introduction (7th Ed.), John Wiley and Sons, Inc. • Askeland, Donald R. and Phule, Pradeep P., (2006) The Science and Engineering of Materials , Thomson • Natividad, Michelle (2006) Classification of Materials. A ppt presentation
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Powerpoint Background: http://martz90.deviantart.com/art/Blue-and-GreenWallpaper-210690826
