Ni-Cr合金真空钎焊金刚石的热损伤分析

Thermal damage analysis of vacuum brazing diamond with Ni-Cr alloy

摘要: 钎焊金刚石工具具有高的出露和连接强度,但金刚石磨料在钎焊过程中所受的热损伤对其寿命影响较大,因此文中对钎焊金刚石的热损伤作了分析.采用Ni-Cr合金对金刚石进行钎焊试验,利用SEM,EDS对金刚石的表面形貌进行观察分析,采用拉曼光谱仪对金刚石表面进行石墨化分析及热应力分析.结果表明,经Ni-Cr合金钎焊后金刚石表面有较多的碳化物(Cr₃C₂,Cr₇C₃)生成,同时发现金刚石表面有少量石墨化和化学侵蚀,其顶部的拉应力大约为110MPa,底部的压应力大约为520MPa.

Abstract: Brazing diamond tools has the characteristics of high protrude and strong bonding,which will be significantly degraded in brazing with the excessively high temperature,and so the thermal damage for the diamond was analyzed.The diamond was brazed in vacuum by using Ni-Cr alloy,then the surface of sample was observed by SEM and EDS,and the heat stress and graphitization on the surface were detected with Laser Raman spectroscopy.The results show that more carbide,such as Cr₃C₂,Cr₇C₃,exists on the diamond surface,and a little graphitization and chemical soakage take place on the surface.The tensile stress in the top of diamond is 110 MPa,and the compressive stress in the bottom of diamond is 520 MPa.