Working Properties Of Materials

Colour:

• Materials are selected because of their natural colour.
• Colour can be enhanced through treatments such as heat,chemicals,pigments,dyes or natural finishes.

E.G Acrylic is often chosen to make signs because it is available in a wide range of bright colours requiring little finishing.

Style:

• Dictated by fashions
• Reconisable by form or decorative details.

E.G An architect restoring an old cottage may choose tradionl materiels rather than modern materiels.

Texture:

• materials are selected because of thier natural textures
• added to materials during manufacturing to improve product appeal (ag moulding, embossing or by adding other materials)

E.G a foam model for a new camera can be enhanced by adding small, self adhesive, paper circles which can be sprayed to give he impression of mould detaiils.

Strength:

• ability to withstand force without breaking or permanent bending
• TENSILE STRENGHT - resistance to stretching forces
• COMPRESSIVE STRENGHT - resistance to pushing forces
• BENDING STRENGHT - resisitance to bending forces
• SHEAR STRENGHT - resistance to sliding/cutting forces
• TORSIONAL STRENGHT - resistance to twisting forces

EG: plastics are more stronger than glass, which is very fragile & breaks easily therefore plastic bottles can be made much lighter than thier glass counterparts

Durability:

• ability to withstand wear & tear
• factors influencing the choice of materials include the required lifespan of the product
• frequency of use
  
• demands placed upon the product
  

EG: polythene bags for shopping will last longer & resist wear more effectively than paper bags

Flammability:

• ability to catch fire
• flammability is affected by material structure, moisture content, shape & form & air circulation
• regulations exist which establish minimum safety standards

EG: highly flammable foams & textile products used in homes must be treated with fire retardant chemicals

Plasticity:

• abilty to deform permanently under pressure

EG: thermoplastics can be moulded when heated

Malleability:

• the extent to which a metal will deform in all dimensions without failing (cracking or rupture)

EG: aluminium can be formed into complex shapes for some car bodies

Ductility:

• the extent to which materials can be drawn down to progressively smaller diameters in one direction without fracturing

EG: copper is formed into long wires

Hardness:

• The ability to withstand wear, scratching & indentation

EG: steel & glass are hard to dent or scratch