Vacuum Brazing of 5CrMnMo Steel and YG8 Hard Metal

The vacuum brazing process of 5CrMnMo steel and YG8 hard metal were studied by using CuMnNi filler metal. Through the methods of hardness testing and DSC, melting temperature of the filler metal was decided. The effects of vacuum brazing temperature and Ni interlayer thickness on bending strength of the brazed joint were studied by the methods of three-bend test, wetting angle test, metallographic analysis and hardness test. The results show that Ni interlayer thickness of adding 0.05 mm under brazing at 1 045℃, the filler metal, the matrix and the interlayer are joined better, and have no defects, at the meantime, the strength of joints is the highest.