Cu-Pd-V钎料真空钎焊Cf/SiBCN复合材料的界面组织与性能

利用Cu-Pd-V钎料对新型四元陶瓷基复合材料C_f/SiBCN进行了真空钎焊连接.利用座滴法研究了Cu-Pd-V钎料对C_f/SiBCN复合材料的动态润湿性.利用SEM和XRD对钎焊接头微观组织及断口物相进行了分析表征.结果表明，经1 170℃保温30 min后钎料在复合材料上的润湿角为57°.在1 170℃-10 min钎焊规范下，Cu-Pd-V钎料在C_f/SiBCN复合材料表面形成厚度约为1 μm的V （C，N）反应层，主要包括VC和VN化合物，钎缝中央为Cu₃Pd和CuPd两种固溶体相.接头的室温三点弯曲强度为58.1 MPa，当测试温度提高至600℃时接头强度上升至90.2 MPa，在700和800℃测试温度下钎焊接头强度呈下降趋势，但仍然可以维持在室温强度水平，分别为66.9和64.6 MPa.

Microstructure and mechanical property of Cf/SiBCN composite joint brazed with Cu-Pd-V filler alloy

Cu-Pd-V filler alloy was used to join C_f/SiBCN composite. Its dynamic wettability on the composite was studied with the sessile drop method. After heating at 1 170℃ for 30 min, the filler alloy showed a contact angle of 57°. The microstructure and phase confirmation of the joint were analyzed by SEM and XRD, respectively. When brazed at 1 170℃ for holding time of 10 min, the interfacial reactions resulted in resulted in the formation of V(C,N) reaction band with the thickness of 1 μm at the surface of C_f/SiBCN composite, and the microstructure in the central part of the joint is composed of Cu₃Pd and CuPd solid solutions. The average three-point bend strength of C_f/SiBCN-C_f/SiBCN joints at room temperature is 58.1 MPa. When the test temperature was increased to 600℃, the average joint strength was even elevated to 90.2 MPa. Eventhough the strength of brazed joints decreased at 700℃ and 800℃, which was 66.9 MPa and 64.6 MPa respectively, it still maintained at room temperature strength value.