What is stainless steel, a common question comes to our mind when we see this metal product. Basically, Stainless steel is an iron-based alloy containing 10.5 percent chromium, carbon, and other non-metals. Chromium enhances the performance of steel against corrosion and high temperature. These steels are known for their hardness and durability. Stainless steels are favorable for those applications that require highly corrosive metals. These steels work well with chemicals, petroleum products, and food industries. Stainless steel is being used in considerable quantities in various sectors. Numerous types of stainless steel are in use today.
Stainless steel can be divided into various types according to their properties and alloy types.
- Austenitic Stainless Steel
Austenitic stainless steel alloys are non-magnetic steel. These are the most demanded types of stainless steel. Austenitic stainless steel has the highest chromium content compared to other steel alloys. That enhances the anti-corrosive properties of these steels. 301, 302, 303, 304, 309, 316, 317, 321, and 347 are austenitic stainless steel grades.
- Martensitic Stainless Steel
Martensitic stainless steel is known for its hardness. Their corrosion resistance is lesser than other alloys. Martensitic stainless steel alloys are favorable for applications requiring high tensile strength and impact resistance. 410, 410S, 414, 416, 420, and 440 are grades of martensitic stainless steel.
- Ferritic Stainless Steel
The third most common type of stainless steel. Ferritic stainless steel is magnetic. These alloys can be hardened through a cold working process. It contains less amount of nickel which leads to a reduction in price. 405, 408, 409, 420, 430, 434, 436, 442, and 444 are grades of ferritic stainless steel.
- Precipitation-Hardening (PH) Stainless Steel
PH stainless steel is known for its corrosive properties with great strength. They have yield strength much better than austenitic stainless steel. They are used in aerospace, nuclear, and oil and gas industries. 17-4, and 15-5 are grades of ferritic stainless steel.
- Duplex (Ferritic-Austenitic) Stainless Steel
These stainless steel alloys are known for excellent corrosion resistance against chloride pitting. Duplex stainless steel is formed after combining ferritic & austenitic This stainless steel has higher tensile strength than austenitic stainless steel. Duplex stainless steel is most favorable for piping in the oil and gas industry. 2205, 2304, and 2507 are grades of duplex stainless steel.