钎焊温度对SiC/YG8接头微观组织的影响

在保温时间为5min、钎焊温度为940~990℃条件下,采用CuMnNi钎料钎焊SiC陶瓷与YG8硬质合金.利用金相显微镜、扫描电镜和能谱仪对接头的微观组织进行分析,研究钎焊温度对接头微观组织的影响.结果表明:在靠近SiC一侧生成一层带状反应层,主要由Cu基固溶体、硅化物、碳和碳化物组成;焊缝主要由基底Cu基固溶体以及Mn、Si、Co、Cu、Ni元素形成的化合物组成.随着钎焊温度的增加,焊缝的宽度减少,焊缝中心的Cu基固溶体基底减少,而化合物相增多.

Effect of Brazing Temperature on Microstructure of SiC/YG8 Joints

SiC ceramics and YG8 hard alloy were brazed using CuMnNi filler metal at 940-990℃ for 5 min. By means of metallographic microscope, scanning electron microscopy （SEM） and energy spectrometer,the microstructure of joint was analyzed, and the effect of brazing temperature on joint microstructure was studied. The results show that at the side of SiC layer, a strip reaction layer was formed,which was composed of Cu-based solid solution, silicide, carbon and carbides; the weld was composed of a basal Cu-based solid solution and compounds of Mn, Si, Co, Cu, Ni elements. With the increasing of brazing temperature, the thickness of brazing seam and the amount of Cu-based solid solution decreases, and the amount of compound phase increases.