AME Unit 1 Q5 – Answer

(a) Cupro-nickel

  • Composition: 60-70% copper, 30-40% nickel, with small amounts of manganese and iron.
  • Applications:
    • Piping systems, heat exchangers, and condensers in seawater systems, due to its excellent resistance to corrosion by saltwater.
    • Propellers, propeller shafts, and hulls of high-quality boats, for its strength and durability.

(b) Aluminium bronze

  • Composition: 90-92% copper, 7-9% aluminium, with small amounts of iron, manganese, and other elements.
  • Applications:
    • Marine hardware, such as propellers, shafts, and fittings, because of its resistance to corrosion and wear.
    • Bearings and gears, for its good strength and wear resistance.

(c) Admiralty brass

  • Composition: 70% copper, 29% zinc, 1% tin.
  • Applications:
    • Condenser tubes and plates in seawater systems, due to its good resistance to corrosion and erosion.
    • Heat exchanger tubes and marine hardware.

(d) Duralumin

  • Composition: 90% aluminium, 4% copper, 1% magnesium, 0.5% manganese, with small amounts of silicon and iron.
  • Applications:
    • Aircraft structures, because of its high strength-to-weight ratio and good fatigue resistance.
    • Marine applications, such as masts and booms, for its strength and corrosion resistance.

(e) Solder

  • Composition: Varies depending on the type of solder, but typically a mixture of tin and lead, with or without other metals such as silver or copper.
  • Applications:
    • Joining electrical components and stained glass panels.
    • Sealing metal cans and food containers.