Vacuum brazing of austenitic stainless steel (SS) under stress with copper-based filler was carried out to assess the susceptibility of liquid metal embrittlement (LME) on stress. Dipping of the SS pipe into molten copper and CuSi3 was performed for comparison. The mechanisms of stress on Cu-SS LME and the effect of Si during cracking were discussed. Test results indicated that microcracks caused by stress concentration increase the possibility of LME. Furthermore, LME was suppressed by the Fe₃Si layer between copper and SS. However, the melting range of the filler extended by the addition of Si increases the probability of LME for longer contacting. Accordingly, the addition of Si into copper-based filler should be avoided for most joining methods of SS with high stress concentration.

使用铜基填料在应力下对奥氏体不锈钢 (SS) 进行真空钎焊，以评估液态金属脆化 (LME) 对应力的敏感性。将不锈钢管浸入熔融铜和 CuSi3 中进行比较。讨论了 Cu-SS LME 上的应力机制和 Si 在开裂过程中的影响。测试结果表明，应力集中引起的微裂纹增加了LME的可能性。此外，LME 被铜和 SS 之间的 Fe ₃ Si 层抑制。然而，通过添加 Si 扩大了填料的熔化范围，增加了 LME 接触更长时间的可能性。因此，对于大多数应力集中的 SS 接合方法，应避免在铜基填料中加入 Si。