Investigation of surface properties of nitrided superalloys

Nickel based superalloys has been using to manufacturing of high temperature parts such as turbine blades jet engines because of the high creep and oxidation resistant widely. But wear resistance of this materials are very low on the contrary of mechanical properties. There are not as many studies on nitriding of nickel base alloys as there are on steels. Nitriding behaviors of nickel based superalloys are very complex and has not been explain completely.In this study, Wirolloy which is a nickel based superalloys was nitrided by plasma nitriding process. It was nitrided under %85 H2+%15 H2 constant gas mixtures and different nitridation conditions such as treatment times and temperatures. Depend on the treatment conditions, structures of nitrided layers and the factors which effect the changing of structures was examined by metallographic inspection and XRD analysis. Mechanical properties and effects of treatment parameters on mechanical properties of nitrided layers was examined by ultra microhardnes and wear testing. After the all investigation, nitriding mechanism of Wirolloy which is a nickel based superalloys was explained.