Study on the cavitation erosion behavior of Fe-based hardfacing alloys containing Mn, Ti and V for replacing Co-based Stellite 6

Abstract

Stellite 6 has been used as hardfacing material of valve components in nuclear power plant industry and other applications. Stellite 6 contains more than 60 wt % Co and it was recognized that Stellite 6 used in valve hardfacing is one of the main sources of Co, which is the major contributor to build up the radiation field in nuclear power plants. Thus it is largely responsible for the occupational radiation exposure of plant maintenance personnel. Also the price of Co is expensive and highly varying. Therefore, there have been many efforts to develop Co-free hardfacing alloy We have also developed Fe-based new alloy, of which sliding wear and cavitation erosion resistance were almost equivalent to those of Stellite 6. In the present study, the effects of Mn, Ti and V on the cavitation erosion behavior of the alloy were investigated. The Fe-based new alloy containing V had similar cavitation erosion resistance to Stellite 6 but the others containing Mn and Ti were inferior to Stellite 6.