Chapter 4: Materials 1. Alloy – a material that is a mixture of metals.

2. Ceramic – a material used for making pottery, bricks, and other products; originated from the Greek word Kermos, meaning “burnt stuff”.

3. Composite – Combinations of different materials.

4. Ferrous – any metal or alloy that contains iron.

5. Hardwood – trees that have broad leaves, which they usually lose in the fall. They are also known as deciduous trees. Ex. Oak Tree.

6. Opaque – an optical characteristic of a material that allows no light to pass.

7. Photosynthesis – the process used by trees and plants to change water and carbon dioxide into carbohydrates using light as an energy source.

8. Primary Material – A natural material; a material that exists in nature.

9. Softwood – Coniferous trees that retain their needlelike leaves and are commonly called evergreen trees (They stay green year-round). Ex. Christmas Tree - Pine

10. Strength – is a mechanical property that measures a material’s ability to resist mechanical forces.

11. Thermoplastic – material that can be repeatedly softened by heating and hardened by cooling.

12. Transparent – An optical characteristic of a material that allows all light to pass.

13. Translucent – an optical characteristic of a material that allows some light to pass.

14. Mechanical Properties – the ability of a material to withstand mechanical forces. Mechanical Properties include: Strength Elasticity Plasticity Hardness Toughness Fatigue