Corrosion resistance in steel is based on a thin passive layer consisting of a chromium rich oxide surfacefilm. The effectiveness of this protective surface film is strengthened with increasing amounts of Cr, Mo andN in solid solution in the steel. However, it is difficult to strongly improve the corrosion resistance and stillmaintain a high hardness and wear resistance in steels relying on carbides as the wear resisting hard phase.To significantly increase corrosion resistance and at the same time achieve hardness around 60 HRC aviable concept is to exchange most of the carbon with nitrogen. This eliminates the presence of thechromium carbide, M7C3, and instead favors the formation of stable and hard phase particle of M2N-typeand MN. In this paper a high nitrogen steel alloy is presented with an amount of hard phase particles of 9vol-%. The bench mark of this grade indicates that the corrosion resistance is similar to or better than 316Stainless steel, but with a higher hardness and wear resistance. A process route based on powdermetallurgy has enabled development of new high nitrogen steel grades with unique property combinationsof hardness, wear resistance, low friction properties and corrosion resistance. This paper presents theproperties profile of the new high nitrogen alloyed steel as well as industrial application results in foodprocessing, plastic molding and wear parts in general engineering.
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