Types of alloy steel
When certain special properties are required some elements such as nickel, chromium, manganese, etc are add in steel. Steel obtain after this called as alloy steel. According to different properties alloy steels are classified in certain types and these are as follow.
- Free cutting steel or Free machining steel
This type of steel is suitable for machining and cutting at high speed because of its high machinability. This steel contain phosphorus, lead, Sulfur, Magnesium, etc which increase machinability of steel.
- High strength low alloy steel
This type of steel mostly use in automotive industry. High strength low alloy steel has good ductility, malleability, formability, toughness and weldability. Some alloy elements uses in high strength low alloy steel are aluminium, boron, copper, lead, chromium, manganese, etc.
- Maraging steel
Maraging steels are known for superior strength and toughness without losing malleability. It is use in rocket and engine component because of its high strength and toughness. Some alloy elements are cobalt, molybdenum, titanium, etc.
- Dual phase steel
Dual phase steels has ferrite–martensite microstructure due to this, this steel is known as dual phase steel. Dual phase steels are obtained from heat treatment process on low or medium carbon steel. The percentage of martensite varies from 15 to 30%.
- Creep resisting steel
This type of steel is use in high temperature application like in thermal power plants. It shows high temperature resistance, oxidation resistance and corrosion resistance properties. Some alloying elements are Tungsten, Molybdenum, Vanadium, Chromium and Cobalt.
- Low expansion steel
These types of steel have very low coefficient of expansion due to this property they are widely used in measurement instruments such as gauges, tapes, macro meter, etc.
- Spring steel
These steels have very high yield strength, fatigue resistance and better elongation. These types of steels widely use in spring or in suspension system because of their properties. It can with stand under compression, tension and torsion loads. Due to this, it is known as spring steels.