Effects of Phase Transformation Temperature on Formation of Wear-Induced Layer in Fe-Ni Alloys

Effects of the transformation temperature on formation behavior of the wear-induced layer in Fe alloys are investigated using Fe-33mass%Ni and Fe-30mass%Ni alloys. Martensitic transformation temperature (M-s) and reverse transformation temperature (A(s)) of Fe-33mass%Ni alloy are lower than those of Fe-30mass%Ni alloy. Microstructure of the wear-induced layer in Fe-33mass%Ni alloy was single austenite phase (gamma) with fine grain. On the other hand, the wear-induced layer in Fe-30mass%Ni alloy consists of martensite (alpha') and gamma with fine structure. This difference is due to the difference of A(s) between these Fe-Ni alloys. Moreover, the microstructure of the wear-induced layer has no dependence on the distribution of alpha' in initial microstructure. From obtained results, it is concluded that the formation of the wear-induced layer in Fe alloys is mainly affected by A(s).