Stainless steel covers a wide range of corrosion and heat-resistant iron-based materials which contains at least 10% of chromium and maximum 1.2% of carbon in addition to other alloying elements. Basically, increasing the percentage of chromium will increase the resistance. There are five basic groups of stainless steel, classified according to their metallurgical structure, namely

• austenitic,
• ferritic,
• martensitic,
• duplex,
• and precipitation-hardening.

Aaustenitic and duplex stainless steels are the most widely used in architecture and structural engineering partly due to their weldability.

PrEN1993-1-2 Annex C provides the material properties for stainless steel of grades 1.4301, 1.4401, 1.4571, 1.4003 and 1.4462 at elevated temperatures. For other stainless steels according to EN1993-1-4, their mechanical properties may be taken as those for hot-rolled carbon steel as given in Section Hot-Rolled Carbon Steel, whereas the thermal properties may be taken from the following section.

Table 1 shows the chemical composition of stainless steel of grades 1.4301, 1.4401, 1.4571, 1.4003 and 1.4462 according to prEN10088-1. Grades 1.4301, 1.4401 and 1.4571 are austenitic stainless steels, whereas grade 1.4003 is ferritic and grade 1.4462 is duplex. It is noteworthy that the mechanical properties and chemical composition of any particular stainless steel may vary between standards and it is important to check properties with individual producers. In this case, according to British Standard grade 1.4404 is equivalent to 316L austenitic grade and grade 1.4462 is equivalent to duplex 2205 grade.