Lesson 1

 application  design of components  material protection (from corrosion, damage, etc.)

1. Physical properties 2. Mechanical properties 3. Chemical properties

 colour –light wave length  specific heat – the heat required to raise the temperature of one gram of a substance by one degree centigrade (J/kg K)

3  density – mass per unit volume expressed in such units as kg/cm 3  thermal conductivity –rate at which heat flows through a given material (W/m K)

 melting point – a temperature at which a solid begins to liquify  electrical conductivity – a measure of how strongly a material opposes the flow of electric current ( Ω ⋅ m)

 coefficient of thermal expansion – degree of expansion divided by the change in temperature (m/°C)

 tensile strength – measures the force required to pull something such as rope,wire or a structural beam to the point where it breaks  ductility – a measure of how much strain a material can take before rupturing

 malleability – the property of a material that can be worked or hammered or shaped without breaking  brittleness –breaking or shattering of a material when subjected to stress (when force is applied to it)

 elasticity – the property of a material that returns to its original shape after stress (e.g. external forces) that made it deform or distort is removed  plasticity - the deformation of a material undergoing non-reversible changes of shape in response to applied forces

 toughness – the ability of a material to absorb energy and plastically deform without fracturing  hardness – the property of being rigid and resistant to pressure; not easily scratched

 machinability – the property of a material that can be shaped by hammering, pressing, rolling

 corrosion resistance - a material's ability to resist deterioration caused by exposure to an environment

MaterialProperties aluminium rubber ceramics steel copper lead nylon cast iron wood

MaterialProperties aluminiumlightness ; strength rubberelasticity ; insulation ceramicsthermal resistivity steelstrength copperconductivity ; corrosion resistance leadhigh density; ductility nylonstrength ; toughness cast irondamping capacity woodinsulation ; environmental friendliness

MaterialApplication aluminium rubber ceramics steel copper lead nylon cast iron wood

MaterialApplication aluminiumfoil; aircraft; window frame rubbertyres,; seal; gasket ceramicsfurnace; brick steelsection; pipe copperpipe; cables leadstorage battery; radiation protection ballast; bullets nylonrope; clothing cast ironengine block; valves woodfurniture; deck

gold kg/m 3 uranium kg/m 3 lead kg/m 3 steel kg/m 3

MaterialTensile StrengthUTS (Ultimate Tensile Strength) carbon nanotubes MPa (theoretical MPa) kNm/kg carbon fibre 5650 MPa 3200 kNm/kg glass fibre 4700 MPa 1340 kNm/kg spider web 1000 MPa 900 kNm/kg high-strength steel 1200 MPa 154 kNm/kg

MaterialConductivity silver 63 x 10 6 S/m (1/ohm) copper 59.6 x 10 6 S/m (1/ohm) gold 45.2 x 10 6 S/m (1/ohm) aluminium 37.8 x 10 6 S/m (1/ohm)

MaterialSpecific resistance (PET) polyethylene terephthalate (PET) ohm glass ohm rubber ohm

Forging - a manufacturing process where metal is shaped by plastic deformation under great pressure into high strength parts. Casting – pouring or injecting molten metal into a mold containing a cavity with the desired shape