Question

State (i) composition (ii) reason for alloying (iii) one use of each of the following alloys.
(i) Brass
(ii) Bronze
(iii) Duralumin
(iv) Solder [fuse metal]
(v) Stainless steel

August 22, 2024

Answer

Alloy	Composition	Reason for alloying	Use
1. Brass	Cu [60 – 80%], Zn [40 – 20%]	Hard, Lustrous, easily cast, malleable, ductile	Electrical fittings, decorative articles
2. Bronze	Cu [80%], Zn [1%], Sn [19%]	Hard, brittle, takes up polish	Statues, medals, coins
3. Duralumin	Al [95%], Mg [0.5%], Mn [0.5%], Cu [4%]	Al – imparts lightness, Mg – imparts strength	Aircrafts, light tools, cooker
4. Solder [fuse metal]	Pb [50%], Sn [50%]	Sn – lowers melting point of alloy	Electrical fuse, Soldering purposes
5. Stainless steel	Fe [75%], Ni [10%], Cr [15%], C [.5%]	Ni, Cr – imparts lustre, C – imparts hardness	Utensils, cutlery, surgical instruments

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