The Study Of YG20 Cemented Carbide Surface Modification By High Current Pulse Electron Beam

Cemented carbides are widely applied in industrial productions areas, which usually serve in hostile environment and are easy to suffer from abrasion, corrosion and fracture. Surface modification processing is the most commonly used for improving the properties and service life of the cemented carbides.YG20 cemented carbide was modified by high current pulsed electron beam under the condition of the accelerating voltage of 23.4kV, pulse duration of 2.5?s and different pulses number of 3,5,10,15,25,35, respectively. The modified surface microstructure was characterized with scanning electron microscope, X-ray diffraction, electron probe microanalysis and transmission electron microscope techniques. The properties after modification were studied by micro hardness, wear resistance and corrosion resistance testing.Crater and microcrack occurred on the surface after HCPEB irradiation. The nano-sized phases WC1-X, Co3W3C and Co3W9C4 graphite were found in the modified coating. The best properties such as surface roughness, micro-hardness and wear resistance were obtained after 25 pulses HCPEB irradiation. After 25 pulses HCPEB treatment, the surface roughness decreased from 0.52?m to 0.09?m, the micro hardness increased from 1170.6HV to 1359HV, and the wear resistance was 2.11 times that of the original sample. The corrosion resistance reached to the optimum value after 10 pulses HCPEB irradiation, which corrosion current density decreased from 17.25 to 2.433?A/cm2. The corrosion current density decreased from 17.25?A/cm2 to 4.860?A/cm2, being 3.55 times of the initial sample after 25 pulses treatment by HCPEB.Micro hardness, wear resistance and corrosion resistance of YG20 cemented carbide are improved effectively by high current pulses electron beam. The results show that the best modification effect is obtained by HCPEB after 25 irradiation processing.