Abstract:

Cr powder was added between Ag-Cu-Zn alloy and diamond grits to braze diamond on the steel substrate by means of high frequency induction heater. Brazing alloy has well wet ability to diamond and the high bonding strength can be achieved between diamond and brazed alloy. By observation of optical microscopy，scanning electron microscopy，electron energy spectrum analysis and X-ray diffraction, the microstructure of the interfaces on steel substrate- brazed alloy-diamond were investigated. Two transition layers are found in the places which the Ag-Cu-Zn alloy is near the steel substrate and the diamond respectively, another transition layer is found on diamond itself. Main reactive phases between Ag-Cu-Zn alloy and diamond are Cr₇C₃ and lead to the high bonding strength between them.

Key words: Ag-Cu-Zn alloy, brazing, diamond, interface

摘要：

在Ag-Cu-Zn合金钎料中添加Cr粉，将混合钎料用于钢基体上的金刚石高频感应钎焊。钎料对金刚石的润湿性较好，具有较强的把持力。采用光学显微镜、扫描电子显微镜、能谱分析和X射线衍射对钢基体-钎料合金-金刚石之间的界面微观结构和反应产物进行了观察和分析，发现在钎料合金靠近钢基体部分、钎料合金靠近金刚石部分以及在金刚石上都存在反应过渡层，且在钎料和金刚石之间的主要反应产物是Cr₇C₃，该反应物是钎料和金刚石之间牢固结合的主要因素。

关键词: Ag-Cu-Zn合金；钎焊；金刚石；界面