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)
 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
Material
aluminium
rubber
ceramics
steel
copper
lead
nylon
cast iron
wood
Properties
Material
Properties
aluminium
lightness ; strength
rubber
elasticity ; insulation
ceramics
thermal resistivity
steel
strength
copper
conductivity ; corrosion resistance
lead
high density; ductility
nylon
strength ; toughness
cast iron
damping capacity
wood
insulation ; environmental
friendliness
Material
aluminium
rubber
ceramics
steel
copper
lead
nylon
cast iron
wood
Application
Material
Application
aluminium
foil; aircraft; window frame
rubber
tyres,; seal; gasket
ceramics
furnace; brick
steel
section; pipe
copper
pipe; cables
lead
storage battery; radiation protection
ballast; bullets
nylon
rope; clothing
cast iron
engine block; valves
wood
furniture; deck
gold - 19300 kg/m3
uranium - 19100 kg/m3
lead - 11340 kg/m3
steel - 7800 kg/m3
Material
Tensile Strength
UTS (Ultimate Tensile
Strength)
carbon nanotubes
62000 MPa
48000 kNm/kg
(theoretical300000 MPa)
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
Material
silver
Conductivity
63 x 106 S/m (1/ohm)
copper
59.6 x 106 S/m (1/ohm)
gold
45.2 x 106 S/m (1/ohm)
aluminium
37.8 x 106 S/m (1/ohm)
Material
Specific resistance
polyethylene terephthalate (PET)
1020 ohm
glass
1014 ohm
rubber
1013 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