C/C复合材料与镍基高温合金GH3128钎焊

Brazing of C/C composite and Ni-based high temperature alloy GH3128

在连接温度为1 170℃、保温时间为60 min的条件下,采用BNi2钎料对C/C复合材料和GH3128进行真空钎焊.利用扫描电镜、能谱仪和X射线衍射仪对接头的界面组织及断口形貌进行分析.结果表明,在钎焊过程中,Cr原子向C/C复合材料侧聚集,并与C原子发生反应生成Cr3C2,改善了BNi2钎料对C/C复合材料的润湿性,从而实现了C/C复合材料与镍基高温合金GH3128的良好结合;C/C复合材料/BNi2/GH3128钎焊接头区域生成Cr3C2,MC,M3Ni2Si,Cr7C3,MB等反应产物.接头的断裂位置发生在靠近C/C复合材料的焊缝区域,接头的抗剪强度为24 MPa.

C / C composite and GH3128 have been vacuum brazed with BNi2 at 1 170 ℃ for 60 min. The microstructure of the joint and the fracture surface were analyzed by scanning electron microscope( SEM),energy dispersive spectrometer( EDS)and X-ray diffraction( XRD). The results show that Cr atom aggregated and reacted with C forming Cr3C2 at the side of C / C composite,which improved the wettability of BNi2 on C / C composite. Thus the metallurgical bonding of C / C and GH3128 were achieved at the bonding zone. Cr3C2,MC,M3Ni2 Si,Cr7C3and MB formed in the brazed joint. The joint failed at the brazing zone near C / C composite,and the shear strength of the joint was24 MPa.