Compared to conventional stainless steels, stainless heat-resistant steels possess higher contents of the alloys carbon, silicon and aluminium. They are special steels for thermal stress at temperatures ranging from 600 °C to 1,150 °C. One of their main properties is their resistance to permanent scaling allowing for different gases. Material selection depends on the existence of sulphurous oxidating, reducing or nitrogenous gases or the danger of carbonisation in the intended application. We can recommend various ferritic or austenitic steels in consideration of the existing temperature and gas media. The main alloying elements form a thick and adhesive surface layer at high temperatures. This surface layer prevents further penetration of reaction products into the surface. For these steels, the scaling resistance is tested, i.e. scaling loss must not be greater than 2 g/m² per hour in a 120 h test. Our customers can choose from ferritic, austenitic and duplex steels.