铜锡钛合金钎焊金刚石及立方氮化硼磨粒界面特征分析

Microanalysis of Interface Characteristics of Brazed Diamond and Cubic Boron Nitride Abrasive with Cu-Sn-Ti Filler Alloy

采用一种铜基合金(Cu-Sn-Ti)作为活性钎料,在高真空炉中钎焊连接金刚石、立方氮化硼与45#钢基体,将其牢固钎焊在基体表面。通过扫描电镜(SEM)、能谱仪(EDS)和X射线衍射仪进一步研究活性元素Ti在Cu基合金与金刚石及立方氮化硼结合界面的扩散现象。结果表明:活性元素Ti向金刚石、立方氮化硼表面发生偏聚,生成Ti C、Ti N、Ti B和Ti B2;活性元素Ti在向金刚石和立方氮化硼磨粒的扩散存在一定的差异性;铜基合金和钢基体的结合界面发生元素扩散生成铁钛金属间化合物。

Diamond and CBN grains were brazed directly onto AISI 1045 steel matrix in the vacuum furnace using Cu-Sn-Ti as active filler alloy. Diffusion phenomenon on the bonding interface between the brazing diamond and CBN abrasive crystals and the filler alloys were investigated by scanning electron microscopy（ SEM）,energy dispersive spectroscopy（ EDS） and X-ray diffraction（ XRD） techniques. The results show that Ti element in the Cu-Sn-Ti alloys diffuses preferentially to the surface of the diamond and CBN to form a Ti-rich reaction layer,which is composed of TiC,TiN,TiB and Ti B2 phases by the Xray diffraction phase analysis. There are some slightly difference of the Ti element diffusion between the brazing diamond and the CBN grains using Cu-Sn-Ti alloy. It also reveals that titanium and iron are mutual diffused to each other on the interface of the alloys and the steel to form iron titanium phase compound.