Stainless steels are divided into four categories, depending on their microstructure at room temperature. Depending on what type of project you are working on, you’ll need a particular type of stainless steel to meet your needs. Here’s a short, quick guide to different types of stainless steel.

Precipitation Hardening and Martensitic Stainless Steel

This category includes steels two different types of stainless steel that have been modified to improve their strength, such as stainless custom 630. Though these metals have high strength and wear resistance, they are not as weldable or formable as austenitic stainless steel. Both stainless steel types in this group are magnetic and offer only limited corrosion resistance.

 

Austenitic Stainless Steel

Austenitic stainless steel has good to excellent resistance to corrosion, so it will not rust easily. It is also non-magnetic and is easy to weld and form into necessary shapes, which makes this steel the best choice for such a purpose. These steels are strong and contain more nickel than other types of stainless and they do not harden with increased temperatures. Aside from that, these metals also take longer to deteriorate under stress and pressure.

Austenitic stainless steels are divided into five subcategories:

  • Cr-Ni grades
  • Cr-Mn grades
  • Cr-Ni-Mo
  • High-performance austenitic
  • High-temperature austenitic grades

Ferritic Stainless Steel

Ferritic stainless-steel grades are alloyed with chromium, but they contain very little, if any, nickel. Because nickel is an expensive alloying element, this keeps the price fairly reasonable. Along with having good weldability, these stainless steels are also tough, magnetic, and offer good corrosion resistance. Carbon is added to some ferritic stainless steels in order to improve resistance to higher temperatures.

Duplex Stainless Steel

Duplex stainless steels combine many of the advantages of ferritic and austenitic stainless steel together. Their microstructure allows them to have high strength and toughness as well as a high resistance under stress. A magnetic and lightweight metal, these stainless steels are easy to form and weld. They have a high chromium content, though a low nickel content helps make them reasonably priced.