1. Warm Up #
What are some physical properties that are used to evaluate materials?

2. Technology and the Design Process
Lesson 2: Materials and Their properties

3. Essential Questions How are materials selected for a designed product?
Why are materials modified to change their properties?
How are materials classified?

4. Properties of Materials
Physical property – a characteristic that can be observed or measured without changing the identity of the material
Include magnetism, conductivity, density, solubility, melting point, and boiling point

5. Physical Properties Activity
Identify the physical properties of the following objects:

6. Properties of Materials
Chemical property – the ability or inability of a substance to combine with or change into one or more new substances
Ex: rust, flammability, burning, corrosive, pH level
Why is the ability to rust a chemical property?

7. Properties of Materials
Mechanical properties – characterizes that determine how a material reacts to forces

8. Types of Materials
Wood – most common material used to build houses, make toys and furniture, provide fuel, etc.
Polymers – natural or manufactured materials composed of long chains of small, repeating molecules
Ex: plastics is an example of this
Plastics – usually lightweight, strong, waterproof, and inexpensive

9. Types of Materials
Composite material – a mixture of 2 or more materials, 1 layered in the other
Used to make automobile bodies strong, lightweight, and rust resistant
Alloy – a mixture of 2 or more materials
Used when the properties need to be improved for an application, like hardness, strength, density, or durability
Ceramics – mixtures that are produces
to achieve desired properties