Outokumpu high-temperature stainless steels have been specifically designed for temperatures up to 1150 °C. This has been achieved by the addition of a number of important alloying elements in the steel – ensuring superior performance across a wide spectrum of high-temperature applications.
High temperature austenitic grades
High temperature austenitic steels are commonly employed in a number of applications where the temperature exceeds 550°C, for instance in equipment and components within the iron, steel and other metallurgical industries, the engineering industry, energy conversion plants and the cement industry.
An important consideration at high temperatures is that creep strength is usually the primary dimensioning factor. This means that by choosing the right material, you not only extend the lifetime of your application, but can also specify a thinner material for overall savings in cost. This applies especially to our high temperature austenitic grades Outokumpu 153 MA™ and Outokumpu 253 MA®.
High temperature ferritic grades
The main alloying element in the ferritic grades is chromium. Its positive effect on the scaling resistance is enhanced by silicon and aluminium.
Ferritic steel grades 4713 and 4724 are best suited for temperatures between 550°C and 850°C. The higher alloyed 4736, 4742, 4762 grades can be applied at temperatures up to 1150°C showing excellent resistance against reducing sulphur attacks and molten metals.
Due to their ferritic structure, the ferritic steels show lower strength at temperatures exceeding 600°C, but are more resistant to thermal shocks than high temperature austenitic stainless steels. With the thermal conductivity higher and the thermal expansion lower than the respective values for austenitic steels, equal thermal shocks will result in lower thermal stresses in the ferritic material. In these terms, ferrites allow greater tolerances for design and operation.
High temperature ferritic grades are mainly used in high temperature applications with sulphurous atmospheres and/or at low tensile loads such as for installations within chemical industry, power industry, metalworking industry and furnace technology.
Put our expertise to work for you - let us help you to select the optimal high temperature steel grade for your application.
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