Abstract Residual stress variations were determined through small- and large-scale specimen welds using neutron diffraction to evaluate the effect of residual stress on the brittle crack propagation path. The results revealed that significant tensile stresses accelerated brittle crack propagation, while compressive stresses obstructed the brittle crack propagation path. The evaluations were performed using small scale specimens, such as CT specimens. To assess the brittle crack propagation arrest toughness, tests with full-scale specimens were performed. The objective was to clarify the mechanism of brittle crack propagation arrest in welds and to establish the basic theory of a welding technique that uses compressive residual stress to prevent brittle fracture.

中文翻译：

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具有焊缝残余应力的焊接接头不稳定断裂现象

摘要 残余应力变化是通过使用中子衍射来评估残余应力对脆性裂纹扩展路径的影响的小型和大型试样焊缝确定的。结果表明，显着的拉应力加速了脆性裂纹的传播，而压应力阻碍了脆性裂纹的传播路径。使用小规模标本进行评估，例如CT标本。为了评估脆性裂纹扩展停止韧性，进行了全尺寸试样的测试。目的是阐明焊缝中脆性裂纹扩展停止的机制，并建立利用残余压应力防止脆性断裂的焊接技术的基本理论。