Diffusion in MC Carbides in High-Speed Steels during High-Temperature Treatments
The microstructure and chemical composition of MC carbides in the modified variants of AISI M2 type high-speed steel after casting, annealing, carburising and subsequent final heat treatment (quenching and tempering) have been studied by focusing on diffusion processes in these carbides and their stability during high-temperature treatments. Significant changes in both the microstructure and chemical composition of the MC carbides as well as in their volume fraction shown to occur in the high-speed steels studied were attributed to decomposition, coagulation and dissolution of these carbides during heat treatments caused by strong diffusion of alloying elements and carbon. It was also shown that boron, in general, strongly suppressed the diffusion of carbon during carburising.
Andreas Öchsner, Graeme E. Murch, Ali Shokuhfar and João M.P.Q. Delgado
A. S. Chaus and M. Beznák, "Diffusion in MC Carbides in High-Speed Steels during High-Temperature Treatments", Defect and Diffusion Forum, Vols. 297-301, pp. 1065-1070, 2010