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Materials
• “Materials can effectively generate and capture students’ interest in science, mathematics, engineering, and technology.”
-Dr. Thomas Strobe
University of Washington
AIM – Products 2 – engr making it work
Why Study Materials?
• Materials in bulletproof vests worn by Police
• Warm, lightweight, waterproof winter coats
• Materials have played a significant role in field of engineering and education
Material Science video Metal rubber video
http://www.alpineco.com/bulletproofvests.htm
FYI
• Interesting points about advanced materials– Markets for advanced ceramics grew from less than $2
billion in 1987 to over $20 billion in 2000– Materials consume up to 50% of manufactured goods cost– According to U.S. Office of Technology, a key to remaining
competitive in the world is to train more scientists and technologists with a broad background in advanced materials
History of Materials Science
• Babylonians first makers of ceramic building materials
• Imprinted clay tablets used to teach trades from parents to offspring in 2200 B.C.
• Time periods named after dominantly-used material
http://www.livius.org/zo-zz/zopyrus/zopyrus.html
Time Periods
1950s - Silicon Photovoltaic Cells & Transistors1958 - Ruby Laser1959 - Integrated Circuit1966 - Fiber Optics1986 - High Temperature Super Conductors
Data Courtesy of Dept. of Energy and Energy Concepts, Inc.
New Materials
• New materials are designed based on need
• Engineers can design without worrying if a material exists for their application
Metal Rubber
Characteristics of Materials
Strength (Stiffness)Ability to resist effects of tension, compression, and torsion forces
DuctilityHow well a material can be shaped without fracturing
Brittleness– When a material will break while undergoing small deformations
Hardness Ability to resist indentation and wear
Elasticity Ability to return to original shape after deformation
Electrical Conductivity Ability to conduct electrons/electricity
Thermal Conductivity Ability to conduct heat
Hardness Ability to resist indentation and wear
Elasticity Ability to return to original shape after deformation
Electrical Conductivity Ability to conduct electrons/electricity
Thermal Conductivity Ability to conduct heat
Classifying Materials
• Metals
• Ceramics
• Polymers
• Composites
Metals
• Earliest used were “native” metals– Copper, Gold, Silver, and Meteoric Iron
• Can be classified as Ferrous or Non-Ferrous– Ferrous
• Contain 50%+ of iron• Attract magnetic materials
– Non-Ferrous• Contain less than 50% iron• Do not attract magnetic materials• Higher corrosion resistance
Metals Mechanical Properties-see characteristics of materials
• Strong• Tough• Malleable• Ductile• Most are
– Opaque– Lustrous– Dense– Good Heat and Electric Conductors– High Melting Point
Metal Facts
• Iron and Steel are 1st and 2nd most commonly used metals
• Aluminum is third– Lightweight– Can be stronger than steel
AIM-Products 2-Materials - Steel
Ceramics
• Derived from Greek word - keramos– Burned material
• Early applications were building materials and containers
• Glass, although considered a ceramic, is a separate part– Lacks crystalline organization
• No orderly atomic structure
http://www.cumi-murugappa.com/useful-articles/industrial-ceramics-products.html
Ceramics
• Clay products • Refractories
– Used in high temperature applications
– Made of clay
• Abrasives– Extremely hard, pure,
ceramic compounds or mixtures
• Glasses
AIM glass production-products 2
What the ancients knew about glass blowing
http://skovsantik.dk/keramik+stentøj.htm
Polymers
• Formed by Greek words:– Poly - Many– Mer - Parts
• Natural Materials– Wood, leather, cotton,
wool, silk, rubber• Polymers processed by
plants and animals– Proteins, Enzymes,
starches, and cellulose• Plasticshttp://www.hydropolymers.com/en/products/pvc/
Plastics
• Polymers and Plastics ARE NOT the same– Plastics are a member of the polymer group
• Are Synthetic Polymers– Thermoplastic
• Can be reformed• Recyclables
– Thermoset• Once set, cannot be softened by heat
More About Polymers
• Are not strong
• Good electrical insulators
• Low melting temperatures
Polyethylene Terephthalate• PETE• Recycle Code - 1• Most comes from beverage
containers• 99% pure, granulated recycled
PETE sells half cost of new PETE• Recycled Uses
– Fiberfill of jackets, strapping, liquid soap bottles, surfboards, paint brushes, tennis ball fuzz, and more beverage bottles
http://www.designinsite.dk/htmsider/mb0011.htm
High-density Polyethylene
• HDPE• Recycle Code - 2• Well-developed process for
recycling• Recycled Uses
– Drain pipes, flower pots, plastic lumber, trash cans, automotive mud flaps, kitchen drain boards, beverage bottle crates, stadium seats, recycling bins, traffic barrier cones, golf bag liners, and toys
http://www.inglass.com/hdpe_bottles.htm
Polyvinyl Chloride or Vinyl
• PVC or V• Recycle Code - 3• Not burned due to release
of hazardous fumes– Dioxins and Furans
• Recycled Uses– Drainage pipes, pipe
fittings, floor tiles, bottles, doormats, hoses, mud flaps
Plastic Separating System
http://www.labs.nec.co.jp/rel/english/topics/t12.html
Low-density Polyethylene
• LDPE• Recycle Code - 4• Burned in incinerator-
powered generators to produce electricity
• Recycled Uses in where color is not important– Garbage can liners, grocery
bags, paint buckets, fast food trays, lawn mower wheels, and automobile battery parts
http://www.pop-international.com/POP/products_plastic.htm
Polypropylene
• PP• Recycle Code - 5• Recycled Uses
– License plate holders, desktop accessories, hanging files, food service trays, flower pots, and trash canshttp://www.cawalker.co.uk/index.asp?id=43
Polystyrene
• PS• Recycle Code - 6• Most challenging to
recycle• Styrofoam cups and
packing material made• Some methods for
recycling in place– Chemists still looking for
more effective ways to recycle huge amounts
How styrofoam is made
http://www.lafourmi.be/contenu/produits/decorer/decorer_polystyrene.html
Composites
• Combination of two or more constituent materials bonded together in an effort to provide better properties than those of the individual materials
• Ubiquitous in recreational equipment
• Used extensively in International Space Station and make over 10,000 pounds of each space shuttle
What consists in a composite?
• Reinforcement– Part that provides strength to composite
• Shape of a fiber, whisker, or particulate
• Boundary in between• Matrix
– Glue that holds everything together
Industry Support
• ASM International (ASMI)– Society for materials
engineers and scientists
– Dedicated to advancing industry, technology, and applications of metals and materials
http://mnasm.org/asmintl.htm
Industry Support
• American Ceramic Society (ACerS)
– Dedicated to dissemination of scientific, commercial, and educational information about ceramic materials and industry