Materials and their working properties · GCSE Design and Technology

Papers, boards and timbers

Papers and boards: layout paper (thin, for sketching), cartridge paper (thicker, for drawing), tracing paper, and bleedproof paper (for marker pens); boards include corrugated card (packaging), duplex board, foil-lined board (food packaging), foam board (models) and corriflute (signs).
Hardwoods come from deciduous trees and are generally dense and durable: oak, ash, beech, mahogany and balsa (which is a hardwood despite being very light).
Softwoods come from coniferous trees and grow faster, so they are cheaper: pine, larch and spruce.
Manufactured boards are made from wood waste or veneers: MDF (smooth and stable), plywood (strong, layers at right angles) and chipboard (cheap, used in flat-pack furniture).

Ferrous metals contain iron and most rust: low carbon (mild) steel, high carbon (tool) steel and cast iron.
Non-ferrous metals contain no iron and don't rust: aluminium (light), copper (conducts electricity well), tin and zinc.
Alloys are mixtures of a metal with other elements to improve properties: brass (copper and zinc), stainless steel (steel and chromium, resists corrosion), high speed steel (for cutting tools).

Thermoforming polymers can be reheated and reshaped many times: acrylic (PMMA), HIPS, PVC, PET and polypropylene.
Thermosetting polymers set permanently when heated and can't be reshaped: epoxy resin, melamine formaldehyde, polyester resin, urea formaldehyde.
Natural textile fibres: cotton and linen (from plants), wool and silk (from animals). Synthetic fibres: polyester, polyamide (nylon) and elastane (Lycra). Blends combine their properties, such as polyester-cotton.
Fabrics can be woven, knitted, or non-woven (such as felt).

Physical properties: absorbency, density, fusibility (can be melted and joined), electrical and thermal conductivity.
Working properties: strength, hardness, toughness, malleability (can be shaped without breaking), ductility (can be drawn into wire) and elasticity.