NCEA L1 Materials Tech cheat sheet
NCEA L1 Materials Tech · Keep the key ideas within reach.
Materials Technology (Level 1)
Materials fall into four families: metals, polymers, ceramics/glasses, and composites; each family has distinct properties of strength, hardness, conductivity, and workability.
Hardwood comes from broad-leaved trees (oak, ash, beech); softwood comes from conifers (pine, fir, spruce) - the terms describe the tree type, not necessarily hardness.
Manufactured boards (MDF, plywood, particle board) are made by bonding wood fibres, veneers, or chips with adhesive; plywood has alternating grain directions for strength.
Ferrous metals contain iron (steel, cast iron) and are magnetic and prone to rust; non-ferrous metals (aluminium, copper, brass) contain no iron and resist corrosion better.
Thermoplastics (acrylic, HDPE, PVC) soften and can be reshaped repeatedly when heated; thermosetting plastics (epoxy, polyester resin) cure permanently and cannot be remelted.
Material properties: strength resists force, hardness resists scratching, malleability allows shaping by hammering, ductility allows drawing into wire, toughness resists impact without breaking.
Composites combine two or more materials (e.g. glass-fibre reinforced plastic) to gain properties neither has alone - usually a fibre for strength in a matrix for shape.
Joining methods: adhesives suit dissimilar or thin materials; mechanical fasteners (screws, rivets) allow disassembly; welding fuses compatible metals; joints must suit the material and loading.
Finishing protects and improves appearance: paint, varnish, stain, oil, electroplating, and anodising; surface preparation (sanding, degreasing) determines finish quality.