Often the multiprocess welders have to weld ad work on stainless steels. The stainless steels, also known as steels that resist on corrosion are part of the iron-base alloys. As commercial welders know, these steels do not rust and have high resistance on the attacks of chemicals, gases and liquids. Most of the stainless steels come with good ductility and low-temperature toughness. MIG welders, Arc welders, TIG welders, and Stick welders, further say that these steels are resistant to high temperatures and show good strength properties. As a rule, the stainless steels contain iron and chromium, which could be varying from 11 to 30 %. It is the chromium that secures the basic corrosion resistance of the stainless steels. In general, there are almost 15 different types of chromium stainless steels.

The commercial welders know that to certain stainless steels is added nickel. These steels are known as chromium-nickel stainless steel. Due to the nickel, the thermal conductivity is reduced and the electrical conductivity is decreased.

The so called chromium-nickel steels are part of the AISI/SAE 300 series of stainless steels. Multiprocess welders say that these are nonmagnetic steels with austenitic microstructure. They have small amounts of carbon, since carbon is not corrosion resistant and is not desirable, especially in the 8% nickel, 18% chromium group.

Stick welders, MIG welders, Arc welders, and TIG welders say that the chromium-nickel alloys sometimes get manganese. The alloys comprising of chromium, nickel and manganese were developed originally to conserve nickel. With them a small portion of the nickel is replaced by manganese.

These steels are nonmagnetic and have an austenitic microstructure. Some stainless steel alloys that multiprocess welders work upon include molybdenum. This is added to the steel to improve its resistance at elevated temperatures and to increase its resistance to corrosion.