Abstract: Effects of quenching temperature and tempering temperature on the properties of BSW T15 steel after vacuum high temperature quenching were studied by means of vacuum quenching and tempering equipment, Rockwell hardness tester and scanning electron microscope, and the cracking reason of the BSW T15 steel during high temperature quenching was analyzed. The results show that the surface hardness is kept in the range of 62.5-64.5 HRC by reducing the quenching temperature by 10 ℃ from 1200 ℃,and the distortion variable is reduced and the quenching cracking is effectively prevented; the distortion variable is reduced to 0.15 mm by adopting appropriate tempering temperature, reasonable tooling and optimized process, and the heat treatment process indexes of the BSW T15 steel meet the process requirements.

Key words: powder metallurgy high speed steel, high temperature quenching, deformation, crack