Effect of Nitrogen and Delta-Ferrite Contents on Mechanical Properties, Corrosion Resistance and Abrasive Wear in Type SCS 13 Stainless Cast Steel

The microstructural features and mechanical properties of SCS 13 steel castings were correlated with nitrogen contents together with the varying concentrations of nickel and other compositions. Delta-ferrite contents varied with the compositions, however, showing relatively lower contents than those predicted by Delong plot. Regression equations were developed among various properties. Tensile strength and abrasive wear were also linearly related to the hardness. Electrochemical measurements showed that the varying chemical compositions and delta-ferrite contents have only a minor effect on the corrosion resistance. Multiple regression analysis was made to explain the contribution of nitrogen, and delta-ferrite, which satisfactorily predicted the yield strength, tensile strength, impact energy and abrasive wear. It was shown that nitrogen causes well-known strengthening effect, and also delta-ferrite is a powerful strengthening element.