Metal Dusting Failure and Its Control

Metal dusting failure is a disintegration of Fe-base and Ni-base alloys to a dust of graphite and metal particles, occurring in carburizing atmospheres with aC>1. An overview of the characteristics and mechanisms of metal dusting failure were undertaken. Influencing factors were expounded and corresponding protection measurements were propounded. The results show that metal dusting failure was mostly occurred at temperatures of 400~800 ℃, and there would no metal dusting failure happening below 400 ℃. The metal dusting failure resistance of Ni-base alloys was superior to that of Fe-base alloys. Protective Cr2O3 film would form with sufficient Cr content to enhance the metal dusting failure resistance. Si and Al elements were also beneficial to anti metal dusting failure. Surface hardening and grain fining could improve the metal dusting failure resistance too.