Question

Give the composition and uses of each of the following alloys. Mention the reason for its use.
(i) Stainless steel
(ii) Duralumin
(iii) Brass
(iv) Magnalium
(v) Solder
(vi) Bronze

Answer 1

The composition and uses of each of the following alloys are given below:

Alloy	Composition	Uses	Reason
(i) Stainless steel	Fe = 75% Ni = 8 – 10 % Cr = 15 –18% C = 0.5 – 1%	It is used to make vessels, automobile parts, furniture, surgical and scientific instruments, etc.	Due to its hardness, resistance to corrosion from chemicals, high tensile strength and lustrous property, it is used widely.
(ii) Duralumin	Al = 95% Cu = 4% Mg = 0.5% Mn = 0.5%	It is used to make aircrafts, automobiles and tools.	Due to its light weight, hardness, ductility and resistance to corrosion, it is widely used.
(iii) Brass	Cu = 55 – 95% Zn = 5 – 45%	It is used to make hardware, electrical fixtures, medals, jewellery, musical instruments, etc.	It is malleable, ductile and lustrous. It is hard and is resistant to corrosion. It is easily cast.
(iv) Magnalium	Al = 70 – 95% Mg = 5 – 30%	It is used to make machine parts, aircrafts and scientific instruments.	Due to its light weight, hardness and resistance to corrosion, it is widely used.
(v) Solder	Pb = 50% Sn = 50%	It is widely used to join wires in electrical instruments and circuits in electronic gadgets.	Due to its low melting point, it is used for soldering.
(vi) Bronze	Cu = 80% Sn = 20%, P, Pb and Zn present in traces.	It is used to make utensils, statues, coins, medals, decorative articles, etc.	It is lustrous after polishing. Due to its hardness, brittleness and resistance to rough usage, it is widely used.