Yang Mengjuan, Niu Chaonan, Hu Shengpeng, Song Xiaoguo, Pei Yinyin, Zhao Jian, Long Weimin
School of Materials Engineering, Shanghai University of Engineering Science, Shanghai 201620, China.
State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, China.
Materials (Basel). 2021 Nov 1;14(21):6570. doi: 10.3390/ma14216570.
The brazing of Titanium alloy to Aluminum alloy is of great significance for lightweight application, but the stable surface oxide film limits it. In our work, the surface oxide film was removed by the ion bombardment, the deposited Cu layer by magnetron sputtering was selected as an interlayer, and then the contact reactive brazing of TC4 alloy to Al7075 alloy was realized. The microstructure and joining properties of TC4/Al7075 joints obtained under different parameters were observed and tested, respectively. The results revealed that the intermetallic compounds in the brazing seam reduced with the increased brazing parameters, while the reaction layer adjacent to TC4 alloy continuously thickened. The shear strength improved first and then decreased with the changing of brazing parameters, and the maximum shear strength of ~201.45 ± 4.40 MPa was obtained at 600 °C for 30 min. The fracture path of TC4/Al7075 joints changed from brittle fracture to transgranular fracture, and the intergranular fracture occurred when the brazing temperature was higher than 600 °C and the holding time exceeded 30 min. Our work provides theoretical and technological analyses for brazing TC4/Al7075 and shows potential applications for large-area brazing of titanium/aluminum.
钛合金与铝合金的钎焊对于轻量化应用具有重要意义，但稳定的表面氧化膜限制了其发展。在我们的工作中，通过离子轰击去除表面氧化膜，选择磁控溅射沉积的铜层作为中间层，从而实现了TC4合金与Al7075合金的接触反应钎焊。分别观察和测试了在不同参数下获得的TC4/Al7075接头的微观结构和连接性能。结果表明，随着钎焊参数的增加，焊缝中的金属间化合物减少，而与TC4合金相邻的反应层不断增厚。随着钎焊参数的变化，剪切强度先提高后降低，在600℃保温30min时获得了约201.45±4.40MPa的最大剪切强度。TC4/Al7075接头的断裂路径从脆性断裂转变为穿晶断裂，当钎焊温度高于600℃且保温时间超过30min时发生沿晶断裂。我们的工作为TC4/Al7075的钎焊提供了理论和工艺分析，并展示了钛/铝大面积钎焊的潜在应用。
