[ Types of stainless steel ]

The stainless steels are presented in three basic groups when getting into groups with metallurgic structures:

Austenitics - Stainless steels linked to chromium and nickel
Ferritics - Stainless steels linked only to chromium
Martensitics - Stainless steels linked only to chromium with residual carbon above 0,10%.
The austenitic steels are leagues of iron, chromium (17 to 25%) and nickel (7 to 20%).

The austenitic steels can be hardened by using cold working (about 4 times); they can be welded easily; they have high ductility; they have high resistance to corrosion; they are appropriate to work with high temperatures (up to 925° C); they are appropriate to work with low temperatures (including cryogenic applications - below 0°) and they are not magnetic. The ferritics steels are basically leagues of iron and chromium (11 to 17%).

When comparing to austenitic steels, the ferritics are more economic; they are welded and with some special cares, they are easily folded, cut, etc.); they are appropriate for temperatures moderately high; their resistance slightly grows when working with cold methods (about 50%); they have high resistance to corrosion under tension and they are magnetic.