Types of stainless steel
Stainless steel contains chromium, molybdenum, and nickel alloying elements in steel, which make it highly corrosion resistance. They do not corrode in most of the environmental condition. Due to this, they are known as stainless steel. They are highly corrosion resistance due to this stainless steel are largely used. Stainless steel identify by three numerical numbers like 304, 310, 440, etc. Stainless steels are classified in four types and these are as follow.
- Austenitic stainless steels
Austenitic stainless steel contains chromium, nickel and manganese. They are non magnetic. Austenitic stainless steel has high strength in high temperature, resist to scaling and better corrosion resistance than other types of stainless steel. Austenitic steels are not hardenable by heat treatment.
- Ferritic stainless steels
Ferritic stainless steel is straight chromium stainless steel. It consist 14 to 27 percent chromium approximately. This can be hot worked or cold worked and it is magnetic.
- Martensitic stainless steels
Martensitic stainless steels found in high or low-carbon steels, contain 11 to 18 percent chromium. Martensitic stainless steel usually tempered and hardened. Tempered steel shows good hardness and high toughness.
- Duplex stainless steels or austenitic-ferritic stainless steels
Duplex stainless steels consist two phases that are austenite and ferrite in metallurgical structure and hence it is also known as austenitic-ferritic stainless steels. It shows High resistance to stress corrosion cracking and high yield stress than austenitics.