Which of the following alloys are correctly matched with their uses? (i) $\mathrm{Li} / \mathrm{Mg}$ armour…
Which of the following alloys are correctly matched with their uses?
(i) $\mathrm{Li} / \mathrm{Mg}$ armour plates
(ii) $\mathrm{Cu} / \mathrm{Be}$ high strength springs
(iii) $\mathrm{Mg} / \mathrm{Al}$ aircraft construction
i, ii only
ii, iii only
i, iii only
i, ii, iii
Solution
$\mathrm{Li}$ and $\mathrm{Mg}$ being hard metals are used as an alloy in armour plates.
$\mathrm{Cu}-\mathrm{Be}$ alloy is used in high-strength springs due to ductility of $\mathrm{Cu}$.
$\mathrm{Mg}-\mathrm{Al}$ alloy is used in aircraft construction as $\mathrm{Al}$ is a versatile metal.