Materials: Generating Interest in Science and Engineering

1. materials

2. “Materials can effectively generate and capture students’ interest in science, mathematics, engineering, and technology.” -Dr. Thomas Strobe University of Washington

3. 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

4. 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

5. 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

6. Time Periods 8000 B.C. - Hammered Copper 7000 B.C. - Clay Pottery 6000 B.C. - Silk Production 5000 B.C. - Glass Making 4000 B.C. - Smelted Copper (Bronze Age) 1000 B.C. - Iron Age 500 B.C. - Cast Iron 300 B.C. - Glass Blowing 105 A.D. - Paper

7. Time Periods 600 - 900 - Porcelain 1540 - First Foundries 1774 - Crude Steel 1789 - Discovery of Titanium 1800 - Battery 1824 - Portland Cement 1850 - Reinforced Concrete 1856 - Bessemer Steel-making Process 1870 - Celluloid Production

8. Time Periods 1871 - Periodic Table 1884 - Nitrocellulose 1886 - Electrolytic Reduction of Aluminum 1891 - Silicon Carbide 1907 - First Totally Synthetic Polymer 1923 - Tungsten Carbide 1930 - Fiberglass 1937 - Nylon 1947 - Germanium Transistor

9. Time Periods 1950s - Silicon Photovoltaic Cells & Transistors 1958 - Ruby Laser 1959 - Integrated Circuit 1966 - Fiber Optics 1986 - High Temperature Super Conductors Data Courtesy of Dept. of Energy and Energy Concepts, Inc.

10. New Materials • New materials are designed based on need • Engineers can design without worrying if a material exists for their application

11. Characteristics of Materials • Strength (Stiffness) • Ability to resist effects of tension, compression, and torsion forces • Ductility • How well a material can be shaped without fracturing • Brittleness • When a material will break while undergoing small deformations

12. Characteristics of Materials • 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

13. Classifying Materials • Metals • Ceramics • Polymers • Composites

14. 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

15. Metals Mechanical Properties • Strong • Tough • Malleable • Ductile • Most are • Opaque • Lustrous • Dense • Good Heat and Electric Conductors • High Melting Point

16. 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

17. Ceramics • Clay products • Refractories • Used in high temperature applications • Made of clay • Abrasives • Extremely hard, pure, ceramic compounds or mixtures • Glasses

18. 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 • Plastics

19. Polymers • Are not strong • Good electrical insulators • Low melting temperatures

20. 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

21. 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

22. 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

23. 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

24. 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

25. Polypropylene • PP • Recycle Code - 5 • Recycled Uses • License plate holders, desktop accessories, hanging files, food service trays, flower pots, and trash cans

26. 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

27. 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

28. What consists in a composite? • Reinforcement • Part that provides strength to composite • Shape of a fiber, whisker, or particulate • Matrix • Glue that holds everything together • Boundary in between

29. Lay Ups • Unidirectional and bidirectional carbon fiber, Kevlar, and plain-weave fiberglass used in lay ups • Composed of consecutive layers of fabric, resin, and sometimes a core material

30. Laid Up By Hand vs. Factory • Form materials on a mold and paint the them on the matrix of resin (epoxy) • My Be Difficult to Use, but inexpensive • Combined by two different parts • Resin • Hardner • Factory has materials with epoxy matrix pre-impregnated into • More expensive • Less mess/easy-use

31. Epoxy Matrix • When mixed, has a specific time to spend in container to be used • “pot life” • Also has prescribed work time based on amount of hardener used • Time available to work with materials by placing and forming into mold/application • Start of hardening process is called “going off” • When matrix “goes off,” little work time remains

32. Effective Lay Up Procedure 1. Fabric is cut to appropriate size 2. Bag, peel ply, perforated plastic, and bleeder cut to appropriate sizes 3. Mold is prepared with gel coat, mold release and/or wax 4. Correct amount of resin and hardener used 5. Pot life is not compromised 6. Material laid up within appropriate work time

33. Industry Support • ASM International (ASMI) • Society for materials engineers and scientists • Dedicated to advancing industry, technology, and applications of metals and materials

34. Industry Support • American Ceramic Society (ACerS) • Dedicated to dissemination of scientific, commercial, and educational information about ceramic materials and industry