DT - Polymers, Timbers & Metals

Revision for term 2 dt test - year 10 Topics: polymers, metals, timbers, surface finishes, properties of materials, papers & boards, design communication

List some surface finishes/treatments used for metals (+outline process)

• Plastic dip coating - Metal is heated and dipped in powdered plastics for protection, insulation & adds a grip

• Powder coating - Dry powder paint is sprayed onto metal after being electrically charged

• Galvanising - Zinc is coated over steel products to protect from corrosion

• Metal lacquer - A clear varnish-like finish, applied to metal to protect and create a sheen gloss or matt finish

List some surface finishes/treatments used for polymers (+outline process)

• Spray paint & primer - plastics are primed and sprayed for aesthetics and protection from UV degradation

• Vinyl decals - Printed and self-adhesive decals can be attached to most surfaces

• Heat transfer printing - Image is printed onto special paper and transferred onto the surface with a heat press

• Polishing - Rubbing & applying a chemical treatment onto a polymer, leaving a clean surface

List some surface finishes/treatments used for timbers (+outline process)

• Painting - Liquid pigment used for aesthetics & resistance to dirt. Con: can appear dull shortly after applying. (reapply every 6-10 yrs)

• Staining - Permanent colour for wood that acts as a sealant, making it waterproof & more natural looking. (reapply 2-3 yrs)

• Varnishing - Glossy transparent film/protective coating that seals & protects wood. Con: yellows with age. (reapply 2-5 yrs)

• Wax - finishing product that soaks into wood to protect it from absorbing moisture (reapply every year)

• Oil - Oils penetrate surface of wood to replenish natural oils & buff away marks (reapply 3-6 months)

What are the 3 types of metals (+ list examples of each)

• Ferrous

• Non-ferrous

• Alloys:

What are the 3 main types of polymers

How is paper manufactured?