Introduction
Austenitic stainless steels are a group of highly alloyed materials which are widely used for their strength and their corrosion resistance in various applications. Alloying elements, such as chromium or molybdenum, combined with a high nickel content, allow them to maintain a good balance of mechanical and physical properties combined with excellent oxidation and corrosion resistance in a wide range of environments. Because of their excellent corrosion resistance, Austenitic stainless steels are often used in applications that require resistance to high temperatures, such as in heat exchangers, boilers and heaters.
High Temperature Properties of Austenitic Steels
From a mechanical point of view, austenitic stainless steels demonstrate their best properties at temperatures slightly below their melting point. At elevated temperatures, their strength usually remains quite high, however, the ductility tends to decrease. In extreme cases, Austenitic stainless steels may suffer from an increase in the Brinell hardness, which is why it is important to choose the right grade and alloy as well as the optimum heat treatment process.
When it comes to their high temperature properties, austenitic stainless steels are placed in a special category called creep-resistant steel alloys. With a higher nickel content, they have better creep strength at high temperatures, which is one of the most important properties to consider when selecting an alloy for high temperature applications. Similarly, the high chromium content provides excellent oxidation and corrosion resistance.
Conclusion
Austenitic stainless steels are highly alloyed materials which provide a good balance of strength and corrosion resistance in various applications. One of their key advantages is their creep resistance at high temperatures, making them suitable for applications such as heat exchangers, boilers and heaters. With appropriate selection of grades, alloying elements and heat treatment, austenitic stainless steels offer exceptional performance in applications that require resistance to high temperatures.
