Alloys can be defined as the homogenous mixture of two or more metals or non metals. Alloying of metals is done to improve the properties of metals such as their hardness, toughness, brittleness, colour and their durability. Here we will discuss some important alloys of steel and their various uses.
1. Stainless Steel
Stainless steel is an alloy of iron, chromium and nickel. The percentage composition of nickel and chromium in stainless steel is 18 %. Stainless steel is resistant to corrosion i.e. it cannot get corroded by the action of water, oxygen gas or any other chemical. That is why it is used for making utensils, knives, scissors, tools, and surgical instruments. It is also used for making tools and equipments for food processing industry and dairy industry.
2. Tungsten Steel
Tungsten steel contains about 15 to 20 % of tungsten, 5% of chromium and a little of vanadium. It has the ability to retain its hardness even at high temperature. It is used for making drilling tools and cutting tools for high speed lathes.
3. Silicon Steel
Silicon steel contains about 15 % of silicon. It is very hard and resistant to acids. It is used for making pumps and pipes for carrying acids. Silicon steel containing up to 35 % of silicon is used for making transformers and electromagnets.
4. Cobalt Steel
Cobalt steel contains about 35 % of cobalt. It has a very good magnetic property that is why it is used for making permanent magnets.
5. Manganese Steel
Manganese steel contains about 7 to 20 % of manganese. It is very hard, tough and resistant to wear and tear. It is used for making steel helmets, rock crushing machinery and burglar proof safes.
6. Nickel Steel
Nickel steel contains about 3.5 % of nickel. It is very hard, elastic and resistant to corrosion. It is used for making bicycle parts and aeroplanes parts like wire cables, gears, drive shafts, and propeller shafts.
7. Chromium Steel
Chromium steel contains about 2 to 4 % of chromium. It has high tensile strength. It is used for making ball bearings, cutting tools and cutlery.
Test your understanding and answer these questions:
- Explain different types of alloys of steel.