Question

Write the composition and its percentage(approx) and uses of the following alloys:

(i) Stainless steel, (ii) Duralumin, (iii) German Silver.

Answer 1

(i) Stainless steel: 18 % $Cr$ 8% $Ni$
Stainless steel is used as building material due to its durability.
(ii) Duralumin: 95%$Al+$ 4% $Cu+$ 0.5% $Mg+$ 0.5% $Mn$
Duralumin is used in wire, rod, and bar for screw machine products, where good machinability and good strength are required. It is also used for aircraft structures, rivets, hardware, truck wheels, screw machine products, and other structural applications.
(iii) German Silver: 60% $Cu+$ 20 % $Zn$ and 20% $Ni$
It is used as a base metal for silver-plated cutlery and other silverware. It is used in zippers, better-quality keys, costume jewellery, for making musical instruments (e.g., flutes, clarinets).