钎焊温度对Cu-Sn-Ti-Ga钎料钎焊金刚石接头组织及性能的影响

Effect of Brazing Temperature on Microstructure and Mechanical Properties of Brazed Diamond with Cu-Sn-Ti-Ga Solder

摘要:

探讨了Cu-Sn-Ti-Ga复合钎料在900—980 ℃钎焊温度下对金刚石/钢进行钎焊连接，研究了钎焊温度对钎焊金刚石微观形貌、界面特征、元素分布变化及力学性能的影响。结果表明，Cu-Sn-Ti-Ga复合钎料在金刚石表面润湿性良好，钎焊界面主要包含Cu_5.6Sn、TiC及富Ga相；随着钎焊温度的提高，金刚石的出露度逐渐降低，石墨化程度逐渐增大，导致钎焊接头的磨削性能呈现先增大后减小的趋势；当钎焊温度为920 ℃时，界面处已形成连续均匀的TiC反应层，反应层厚度为0.31 μm、硬度达到最大值为310 HV_0.1；金刚石试样的磨损形式表现为均匀磨损，钎料对金刚石的把持力较高。本研究为低成本钎料的发展和应用提供了理论基础。

Abstract:

In this work， a Cu-Sn-Ti-Ga composite filler was employed for brazing diamond to steel within the temperature range of 900—980 ℃. The impact of brazing temperature on the microstructure， interface characteristics， element distribution， and mechanical properties of the brazed diamond were systematically investigated. The results showed that the filler exhibited excellent wettability on the diamond surface， with the brazing interface layer predominantly composed of Cu_5.6Sn， TiC and a Ga rich phase. With the increase of brazing temperature， the exposure of diamond gradually decreased， the graphitization degree of diamond increased， and the grinding performance of the brazed joints exhibited an initial increase followed by a subsequent decrease. Notably， at a brazing temperature of 920 ℃， a continuous and uniform TiC reaction layer with a thickness of 0.31 μm formed at the interface. Microhardness tests showed that the diamond hardness reached a maximum value of 310 HV_0.1， exhibiting uniform wear， and the solder demonstrated a robust holding force on the diamond. This investigation provides valuable insights for the development and application of low-cost brazing materials， offering a theoretical foundation for future advancements in this field.