High Temperature Oxidation Investigation of Hot Roll Material with High-Speed Steel

High-speed steels are successfully manufactured to make work rolls in hot rolling steel mills. An understanding of their oxidation behaviour is crucial to the degradation of work rolls and the surface quality of rolled strip. In this paper, the high temperature oxidation behaviour of a work roll with high-speed steel material was investigated under isothermal conditions from 550 to 750 °C for 30 min in 20% humid air. The results indicate that molybdenum-rich carbides M2C are oxidised and protrude out of the surface, vanadium-rich carbides MC and iron and chromium-rich carbides are easily identified and less influenced, but the oxides grown on the matrix are relatively even at 550 and 600 °C. However, at higher temperature, MC carbides are severely oxidised and extend to their nearby areas, whereas M7C3 zones can still be recognised but with more small particles grown on them.