Vacuum diffusion welding of dissimilar materials of M2/40Cr

The vacuum diffusion welding of high speed steel W6Mo5Cr4V2(M2) with alloy structure steel 40Cr was studied by means of hardness test, tensile test, bending test, scanning electron microscope and OM analysis.Results show that sound metallurgical bonding is obtained between the two dissimilar materials at 1 100℃ for 30 minutes, which bonding pressure is 20 MPa and the vacuum level is not less than 0.1 Pa.The fractures of tensile test and bending test both take in place on the steel of 40Cr.So the strength of bonding zone is higher than 40Cr matrix.Ionnealing after quenching treatment at atrelatively lower temperature can ensure the required hardness of both the high speed steel and the structural alloy steel.