chemistry

ALLOY & THEIR COMPOSITION

	Alloy	Composition		Uses
	Invar	64% Fe, 35% Ni. Mn and C in		To  make  pendulum  rods,  due  to  low
		trace amounts.		temperature coefficient
	Nichrome			To manufacture heating elements of stoves
60% Ni, 25% Fe 15% Cr.			and Furnaces
Non – Ferrous alloys

	Type metal	60–80 % Pb, 13–30% Sb,	Used for sharply defined castings
		3–10% Sn.
	Wood’s metal	50% Bi, 25% Pb, 12.5% Sn,	In automatic alarams. Sprinklers systems
		12.5% Cd,
	Devarda’s Alloy	50% Cu, 45% Al, 5% Zn	To reduce nitrites and nitrates to NH3
	Solder metal	50% Sn, 47.5% Pb, 2.5 % Sb	Electrical appliances
	Duralumin	95% Al, 4% Cu, 0.5% Mn,	Aircraft
		0.5 %Mg.
	Magnalium	85-99% Al, 1–15% Mg	Balance  beams,  aircraft  parts,  motor
			spares
	Aluminium	88–90% Cu, 10–12% Al	Ornaments, Photoframes, coins
	Bronze
	German silver	50–60% Cu, 10–30 % Ni,	Spoons, forks, Utencils
		20–30% Zn
	Bell metal	80% Cu, 20% Sn	Bells
	Bronze	75 – 90% Cu, 10 –25% Sn	Utensils, Coins and statues
	Gun metal	88% Cu, 10% Sn, 2% Zn	Bearings, guns
	Brass	60–80% Cu, 20–40 % Zn	Machine parts
	STEELS :
	Name of the steel	% of the element present	Uses
	Nickel steel	2.5 – 5 % Ni, Fe, C	Cable wires, guns
	Manganese steel	10– 14% Mn, Fe, C	Ball mills, Helmets
	Chromium steel	5 – 15% Cr, Fe, C	Kitchen ware, Razorblades
	Tungsten steel	6–8% W; 14–20% Fe, C	Magnets, Electric motors