materials

• Corrugated Cardboard


  • Has three layers
  • Made by passing papers through a corrugation machine
• Making the centre layer of corrugated cardboard

  1. Steamed to soften the fibres

  2. Crimped to give it a wavy shape
• Assembling corrugated cardboard


  Two outer layers of paper are glued on each side of the wavy centre layer
• Processing corrugated cardboard


  1. Cut into large pieces or 'blanks'

  2. Then go to other machines for printing, cutting and gluing together
• Double Walled Corrugated Card

  • Has an additional wavy and flat layer
  • Makes it more rigid and gives extra protection
• Corrugated card


  • Lightweight yet strong
  • Difficult to fold
  • Good heat insulator
• Ore


  Rock embedded with metals found in the earth's crust
• Extracting ore


  Can be open cast mined, underground mined or dredged from rivers
• Extracting iron from haematite

  1. Ore must be smelted to release metal from the rock

  2. Heated to a very high temperature in a blast furnace
• Aluminium


  Smelted from its ore (bauxite) in a reduction cell
• Ferrous metals


  • Cast iron
  • Mild steel
  • Medium-carbon steel
  • High-carbon steel
• Cast iron


  • Hard surface but brittle soft core
  • Strong compressive strength
  • Poor resistance to corrosion
  • 1200°C melting point
  • Good electrical and thermal conductivity
  • Cheap
• Mild steel


  • Good tensile strength
  • Tough
  • Malleable
  • Poor resistance to corrosion
  • 1500°C melting point
  • Good electrical and thermal conductivity
  • Cheap
• Medium-carbon steel


  • Good tensile strength
  • Tougher and harder than mild steel
  • Poor resistance to corrosion
  • 800°C melting point
  • Good electrical and thermal conductivity
• High-carbon steel


  • Hard but also brittle
  • Less tough, malleable or ductile than medium-carbon steel
  • Poor resistance to corrosion
  • 1500°C melting point
  • Good electrical and thermal conductivity
• Annealing


  A method of heat-treating metals that makes it as soft as possible
• Hardening


  A method of heat-treating that makes metal hard but brittle
• Tempering


  A method of heat-treating metal that reduces brittleness
• Non-ferrous metals


  • Aluminium
  • Copper
  • Silver
• Aluminium


  • Lightweight
  • Soft
  • Ductile
  • Malleable
  • Good conductor of heat and electricity
  • Corrosion resistant
  • 660°C melting point
• Copper


  • Extremely ductile and malleable
  • Excellent conductor of heat and electricity
  • Easy to solder
  • Corrosion resistant
  • 1084°C melting point
• Silver


  • Soft
  • Precious metal
  • Extremely resistant to corrosion
  • Excellent conductor of heat and electricity
  • 961°C melting point
  • Expensive
• Plastics (synthetic polymers)


  • Polyester
  • Nylon (polyamide)
  • Polypropylene
  • Acrylic
  • Elastane, lycra
  • Aramid fibres
• Polyester


  • Strong when wet and dry
  • Flame resistant
  • Thermoplastic
  • Hard wearing
  • Poor absorbency
• Nylon (polyamide)


  • Strong and hard wearing
  • Melts as it burns
  • Thermoplastic
  • Good elasticity
  • Poor absorbency
• Polypropylene


  • Thermoplastic with low melting point
  • Strong
  • Crease resistant
  • Non-absorbent
  • Resistant to chemicals
  • Hard wearing and durable
• Acrylic


  • Strong except when wet
  • Thermoplastic
  • Burns slowly then melts
  • Poor absorbency
• Elastane, lycra


  • Very elastic and stretchy
  • Lightweight
  • Strong and hard wearing
• Aramid fibres


  • Engineered for strength and heat resistance
  • No melting point
  • Five times stronger than nylon
  • Resistant to abrasion
  • Low shrinkage
  • Easy of care