classification of materials

Ferrous metal

A metal containing mostly iron and carbon; these metals are magnetic and will rust.

Non-ferrous metal

A metal that does not contain iron; these metals are not magnetic and do not rust.

Alloy

A metal made of two or more metals, or combining two or more elements, one of which must be a metal.

Hardwood

Wood from broad-leafed, deciduous trees that are generally slow growing and lose their leaves in autumn.

Softwood

Wood from coniferous, cone-bearing trees that are generally fast growing and tend to be evergreen.

Manufactured board

A man-made wood-based composite material available in much larger sizes than solid wood.

Thermoplastic

a material which can be repeatedly reheated and reshaped, allowing it to be recycled after its initial use.

Thermosetting polymer

a material which when heated undergoes a chemical change whereby the molecules form rigid cross links

Thermosetting polymers cannot be reheated and reshaped, even at very high temperatures.

Elastomer

A material which at room temperature can be deformed under pressure and then upon release of the pressure, will return to its original shape.

Compliant materials (paper and boards)

A classification for papers and boards meaning they can be scored, folded, and cut with basic tooling.

Composite (paper and boards)

A material comprised of two or more different materials, resulting in a final material with enhanced properties.

Stock form

The set of standard sizes in which materials are available for purchase and use.

Mechanical properties

Properties associated with how a material reacts to an external force.

Physical properties

Properties associated with the actual make-up or structure of the material.

Compressive strength

The ability to withstand being crushed or shortened by pushing forces (compression).

Tensile strength

The ability to resist stretching or pulling forces (tension).

Bending strength

The ability to resist forces that may bend the material.

Shear strength

The ability to resist sliding forces on a parallel plane.

Torsional strength

The ability to withstand twisting forces from applied torque or torsion.

Hardness

The ability to resist abrasive wear such as scratching, surface indentation or cutting.

Toughness

The ability to absorb impact force without fracture.

Plasticity

The ability to be permanently deformed (shaped) and retain the deformed shape.

Ductility

The ability to be drawn out under tension, reducing the cross-sectional area without cracking, such as stretching a material into a wire.

Malleability

The ability to withstand deformation by compression without cracking; this increases with a rise in temperature.

Elasticity

The ability to be deformed and then return to the original shape when the force is removed.

Electrical conductor

A material that allows the flow of electrical current, giving very little resistance to the flow of charge.

Electrical insulator

A material that does not allow the flow of electricity to pass through it.

Thermal conductor

A material that allows the transfer of heat energy to occur quickly across it.

Thermal insulator

A material that prevents the transfer of heat through it.

Thermal expansion

The increase in material volume in response to a heat input.

Opaque

A property of a material that prevents light from travelling through.

Translucent

A material that allows light through but diffuses it so that objects appear blurred, such as frosted glass.

Transparent

A material that allows light to pass through easily, meaning you can see clearly through the material.

Density

The mass of the material in a standard volume of space.

Fusibility

The ability of a material to be fused or converted from a solid to a liquid or molten state, usually by heat.

Magnetism

The natural force between objects that causes the material to attract iron or steels.

Corrosion/degradation resistance

The ability of the material to withstand environmental attack and decay.

Materials classification groups

The seven groups include metals, woods, polymers, papers and boards, composites, smart materials, and modern materials.

Smart material

A material whose physical properties change in response to an input or change in the environment, such as electricity, pressure, temperature or light.

Modern material

A material developed through the invention of new or improved processes, such as man-made materials or human intervention, which does not react to external change.

Material disposal

A consideration at the end of a product's life that influences manufacturer material choice and the decisions of environmentally aware consumers.