The microstructure and mechanical properties of high carbide high chromium steel and grey cast iron centrifugal bimetal castings after quenching in 20~# machine oil or water, then tempering were researched.The better heat treatment technology is as follows: quenching at 1020℃ + tempering at 500℃.The average hardness of the samples is 85.1HSD(oil),84.1HSD(water) respectively; the microstructure of high carbon high chromium steel was tempering martensite,carbides and a little remaining austenite; the microstr...