Bayar Stainless Steel Co. Inc.

STAINLESS STEEL CLASSES AND USAGE AREAS

The most important alloying elements that determine the internal structure of stainless steels are chromium, nickel, molybdenum and manganese, in order of importance. Of these, chromium and nickel determine whether the internal structure is ferritic or austenitic.

Austenitic:
It is the most used type of stainless steel. This group includes the most commonly used 304, 316 quality steels and high alloy 310S quality steels. It contains min. 7% nickel makes the steel structure completely austenitic. Nickel imparts ductility, wide temperature range operation, non-magnetic properties, and good weldability. Austenitic stainless steel applications include Housewares, containers, industrial piping and vessels, architectural facades and building structures.

Ferritic :
These are low-carbon stainless steels containing 12% - 18% chromium. The most commonly used type is 430 grade steels. They are similar to mild steels in terms of structure, but they have high corrosion resistance. The main uses of ferritic steels are; kitchen utensils, washing machines, interior decorative applications, automobile chassis parts, exhaust elements, hot water tanks.

Austenitic-ferritic (Duplex):
Due to its internal structure consisting of austenitic and ferritic phases, they are called duplex stainless steel. They are steels containing high levels of chromium 18-28% and moderate amounts of Nickel (4.5% -8%) in the alloy. 8% nickel content is insufficient for full austenitic structure. Its duplex structure provides both strength and ductility. Duplex steel is mostly used in the petrochemical, paper and shipbuilding industries.

Martensitic :
It contains 0.1% carbon and 11-13% chromium. They have moderate corrosion resistance. Heat treatment can be applied and hardnesses can be obtained. This steel is mostly used in turbine blades and blades surgical instruments.