There are many type of steels, which differ from each other in the corrosion resistance, which is provided by a specific factor. According to the chemical composition, the stainless steels are classified at ferritic, martensitic, austenitic and austenitic-ferritic.
This steel is magnetic and sufficiently ductile. The higher content of chromium increases its corrosion resistance, which in oxidizing environments is higher than for martensitic steel. It is used in the chemical industry, in a nitric acid environment, in transportation, climate control, and architecture. It is not suitable in welded structures.
The corrosion resistance is low and drops with increasing temperature. Resistance to atmospheric corrosion is sufficient only in very clean air.
It has high corrosion resistance in all basic classes, and it can be increased by adding molybdenum and copper. An important feature is its ductility and toughness.
It is made from conventional austenitic steel by increasing the chromium content and decreasing the nickel content. This steel therefore has several special properties. Welding is more demanding.