ferrous and non-ferrous metals

• Where are most metals found?

  In the Earth's crust as ore
• What is ore?

  Rock that contains metal
• How can ore be mined?

  Opencast, underground, or dredged
• What is the ore from which iron is extracted?

  Haematite
• Which countries are known for haematite?

  Brazil, Australia, and South Africa
• What must be done to ore to release the metal?

  It must be smelted
• How is iron extracted from haematite?

  By heating in a blast furnace
• What is the ore from which aluminium is smelted?

  Bauxite
• What is a reduction cell used for?

  To smelt aluminium from bauxite
• What do all ferrous metals contain?

  Iron
• What is produced when ferrous metals are alloyed with carbon?

  Steel
• What are the common ferrous metals and their properties?

  • Cast iron: Hard surface, brittle core, strong, cheap
  • Mild steel: Good tensile strength, tough, malleable, cheap
  • Medium-carbon steel: Tougher, harder than mild steel
  • High-carbon steel: Hard but brittle, less tough
• What is the melting point of cast iron?

  1200°C
• What are common uses of mild steel?

  Car bodies, nuts, bolts, screws
• What is the melting point of high-carbon steel?

  1500°C
• What is annealing in heat treatment?

  Heating metal to red heat, cooling slowly
• What does hardening do to ferrous metal?

  Makes it hard but brittle
• What is tempering in heat treatment?

  Heating steel to reduce brittleness
• What is case hardening?

  Hardening the surface of a ferrous metal
• What do non-ferrous metals not contain?

  Iron
• What are common non-ferrous metals and their properties?

  • Aluminium: Lightweight, ductile, corrosion resistant
  • Copper: Ductile, excellent conductor, corrosion resistant
  • Silver: Soft, precious, excellent conductor
• What is the melting point of aluminium?

  660°C
• What is the melting point of copper?

  1084°C
• What is the melting point of silver?

  961°C
• How can the properties of non-ferrous metals be altered?

  By using heat at lower temperatures
• What is an alloy?

  A metal made from two or more elements
• What are common alloys and their properties?

  • Stainless steel: Corrosion resistant, tough
  • High-speed steel: Very hard, friction resistant
  • Brass: Strong, ductile, corrosion resistant
  • Bronze: Harder than brass, corrosion resistant
• What is the melting point of stainless steel?

  1510°C
• What is the melting point of high-speed steel?

  1540°C
• What is the melting point of brass?

  930°C
• What is the melting point of bronze?

  1200°C-1600°C
• What is the melting point of pewter?

  170°C-230°C
• What is the melting point of duralumin?

  660°C
• What are the ecological and social impacts of metal?

  • Creates employment
  • Hazardous working conditions
  • Landscape scars and deforestation
  • Non-biodegradable and polluting
  • Repairable and recyclable
• How much energy can recycling metal save?

  Up to 90 percent
• What is the life cycle of metal products?

  1. Ore dug from ground
  2. Transport
  3. Melted down
  4. Converted to metal
  5. Product manufactured
  6. Disposal
• What are the functional and aesthetic properties of metals?

  • Functional: Strength, durability, conductivity
  • Aesthetic: Finish, shape, color
• What is the impact of processing ore into pure metal?

  Uses a lot of energy
• What is the availability of metal in stock forms?

  Available in various sizes and shapes
• How does the cost of metals vary?

  Common metals are inexpensive, precious metals are expensive