Answer the following in complete sentences:

1. How is controlling light useful to humans? Provide 2 examples in your answer.

2. What are two biotechnologies that have positively impacted your life?

April 29, 2008

DRILL

U3h – L2

U3h – L2

• The technology of producing, altering, and combining materials.

Example applications:

•Producing paper from wood,

•Producing aluminum from ore,

•Drilling holes in wood,

•Annealing to soften metal,

•Laminating wood.

Materials Technology

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“Since the birth of materials science and engineering, materials researchers have

consistently improved materials that have, in turn, enhanced the performance of the

technologies that used them.”

Ivan Amato, Stuff: The Materials The World Is Made Of

Materials Technology

Materials Technology

What are some examples of improved materials that have enhanced the performance of technology?

1. Aluminum baseball bats2. Vinyl siding on houses3. Fiberglass auto-body parts4. Plexiglas 5. Bonded polyurethane vehicle structures6. High strength steels in car frames7. Advanced alloys in airplane engines8. Polymer composites in airplane wings9. Chromium steel alloy bicycle frame

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Materials Technology

What are materials?

Everywhere we look we see products made from materials.

1. The walls around us

2. The floor beneath us

3. The pen/pencils in our hands

4. The paper in our notebook

5. The clothing on us

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Materials Technology

Three categories of materials:

(Remember from looooong ago…)

1. Natural – found in nature

2. Synthetic – human-made

3. Composite – Mixture of both

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Product Performance – the physical properties of a material are a basic reason for selecting the material

Mechanical: tensile strength, fracture toughness, fatigue strength, creep strength, hardness, etc.

Electrical: conductivity or resistivity…

Magnetic: magnetic susceptibility, saturation magnetization…

Optical: polarization, capacitance, absorption…

Thermal: coefficient of thermal expansion, heat capacity, thermal conductivity…

Environment-related: corrosion behavior, wear behavior…

Materials Technology

Materials Technology

Most products are made from different combinations of the various generic materials:

Metals:

• Normally combinations of "metallic elements"• Usually have free electrons • Good conductors of heat and electricity• Strong but malleable • Lustrous (shiny, reflective) look when polished

General

Materials Technology

Ceramics:

Generally compounds between metallic and nonmetallic elements (oxides, nitrides, and carbides)

Insulating

Resistant to high temperatures and harsh environments

Materials Technology

Plastics (or polymers):

• Organic compounds based upon carbon and hydrogen• They have very large molecular structures• Low density and are not stable at high temperatures.

Derived from living organisms

Materials Technology

Semiconductors:

Electrical properties intermediate between metallic conductors and ceramic insulators

Electrical properties are strongly dependent upon small amounts of impurities.

Materials Technology

Composites:

More than one material type

Fiberglass, a combination of glass and a polymer, is an example

Concrete and plywood are other familiar composites

Ceramic fibers in metal or polymers

Materials Technology

Paying attention to the materials in your life generates an endless stream of fascinating questions:

• Why is a skyscraper’s frame made of steel and not copper or polyethylene?

• What is so special about the silicon crystal that it became the foundation of a society-changing electronics revolution?

• How did humans learn to transform the raw stuff of the wilderness into the wondrous contemporary array of materials?

U3h – L2

U3h – L2