Ni-based alloys are believed to be the most suitable brazing fillers for SiC ceramic application in a nuclear environment. However, graphite, which severely deteriorates the mechanical property of the joint, is inevitable when Ni reacts with SiC. In this paper, Different amounts of Zr powders are mixed with Inconel 625 powders to braze SiC at 1400 °C. When Zr addition reaches 40 wt%, the brazed seam confirms the absence of graphite. This research proves that Zr can avoid the graphite’s formation by suppressing Ni’s activity. The room-temperature shear strength of the joint with graphite’s absence is tested to be 81.97 MPa, which is almost three times higher than that of the joint with graphite. The interfacial reaction process and mechanism of the SiC joint are investigated and explained in this paper using thermodynamic calculations.

镍基合金被认为是碳化硅陶瓷在核环境中应用的最合适的钎料。然而，当Ni与SiC反应时，严重恶化接头机械性能的石墨是不可避免的。在本文中，将不同量的 Zr 粉末与 Inconel 625 粉末混合以在 1400 °C 下钎焊 SiC。当 Zr 添加量达到 40 wt% 时，钎焊缝证实没有石墨。该研究证明 Zr 可以通过抑制 Ni 的活性来避免石墨的形成。经测试，无石墨接头的室温剪切强度为81.97 MPa，几乎是石墨接头的三倍。本文使用热力学计算研究和解释了 SiC 接头的界面反应过程和机理。