1. Materials Part 1: Properties of wood and metals
Chapter 1
Materials
Part 1: Properties of wood and metals

2. Materials part 1 Learning Objectives
By the end of this lesson you will have developed a knowledge and understanding of:
what each of the properties of a material means
the working characteristics of common forms of materials
how these materials are made and what happens to them at the end of the usable life of the product
the differences between softwood and hardwood and between natural timber and manufactured boards
the difference between ferrous and non-ferrous metals
how the properties of metals can be changed by heat treatment.
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3. Material properties
Mechanical properties are about how the material reacts when a force is applied to it.
Physical properties are characteristics of the material which are not affected by applying a force to it.
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4. Mechanical properties
Strength:
tensile
compressive
shear
torsion
bending
Hardness
Elasticity
Flexibility
Malleability
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5. Physical properties Corrosion resistance Thermal conductivity
Electrical conductivity
Density
Strength-to-weight ratio
Aesthetic qualities
Sustainability
Cost
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6. Classes of material Groupings based on what they are made from: wood
metal
polymers (plastics)
ceramics
composites
Groupings based on the material properties:
smart materials
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7. Wood – hardwood From deciduous trees that lose their leaves in winter:
beech
ash
elm
oak
mahogany
teak.
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8. Wood – softwood From coniferous trees that stay green all year round:
redwood
western red cedar
parana pine
whitewood.
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9. Market forms of wood Standard timber sizes Typical planed timber sizes
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10. Market forms of wood Timber mouldings
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11. Types of manufactured board
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12. Metals Ferrous metals which contain iron: cast iron steel
stainless steel.
Non-ferrous metals which do not contain iron:
aluminium
copper
brass.
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13. Market forms of metal
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14. Heat treatment
Heat treatment can be used to change the properties of metals:
Quenching and tempering: Hardens and toughens high carbon steels.
Case hardening: Hardens the surface of low carbon steel.
Normalising: Makes work hardened steel tough and ductile.
Annealing: Makes work hardened metals softer and easier to work.
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15. Heat treatment Structure of steel at different temperatures
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