1. Materials Technology Properties of Materials

2. Overview – Properties of Materials OPTION The student will learn about… Grouping of materials according to properties of electrical and thermal conductivity, thermal expansion, optical, magnetic and mechanical properties

3. It is the arrangement of atoms within a material that greatly influences that materials behaviour and it’s properties Hardness Ductility Malleability Conductivity Thermal expansion Optical properties Magnetic properties Melting point, etc. Why would I need to know the properties of a material? Overview – Properties of Materials

4. Materials listed in order of hardness: Diamond Cubic boron nitride (ceramic) Carbides Hardened steels Cast irons Copper Acrylic Aluminium Lead Diamond’s are very hard. I wonder what else could I use them for besides jewellery? Overview – Properties of Materials

5. Materials listed in order of ductility Gold Silver Aluminium Copper Steel What property of a material is Ductility? Overview – Properties of Materials

6. Materials listed in order of malleability Gold Silver Aluminium Copper Tin Lead Steel What material are soft drink cans made from? Why is this material used for the can? Overview – Properties of Materials

7. Materials listed in order of tensile strength Steel Copper Aluminium Zinc Lead What material is used here to support the bridge & why? Overview – Properties of Materials

8. M aterials listed in order of electrical conductivity Copper Cobalt Iron Zinc Aluminum Titanium Magnesium Gold Lead Platinum Mercury Tin Silver Nickel Silicon What material is used in Electrical Wiring. Why is gold or lead not used in electrical wiring? Overview – Properties of Materials

9. Materials in order of thermal conductivity Silver Copper Gold Aluminum Magnesium Silicon Zinc Cobalt Nickel Iron Platinum Tin Lead Titanium Mercury Overview – Properties of Materials

10. Overview – Testing Materials Materials in order of magnetic properties While most materials can be influenced in some way by a magnetic field, Iron, Nickel and Cobalt are thousands of times more susceptible than other materials Iron Nickel Cobalt Compounds containing these elements are also magnetic

11. Selection of Materials Why are electrical wires generally made from copper? Why are airplane bodies usually made from aluminium or composites? Why are cookware handles generally made from wood or plastic? What properties make ash a suitable material for hurleys?

12. Selection of Materials Physical Properties In answering the previous questions we have seen that the physical properties of a material have a large part to play in its selection for a particular application. Hardness, ductility, density, conductivity, melting point, cost of raw material, suitability for recycling, ease of manufacture, etc.