As the development of the polar region continues to increase, the fatigue properties of structures at low temperature are increasingly receiving researcher attention. This study aimed to investigate the fatigue properties of T-welded and cruciform welded joints at −60 °C. Logarithmic S–N curves based on the hot-spot stress of the T-welded and cruciform welded joints at 50% and 95% confidence levels were obtained at −60 °C. The test results showed that the fatigue properties of T-welded joints were almost 2–7% better than those of the cruciform welded joints at −60 °C. Factors that affected the fatigue properties of welded joints, such as the stress concentration factor, microstructure, Vickers hardness profiles, and fractography, were also studied and the test results showed that the fatigue properties of cruciform welded joints at −60 °C were 57.215% better than at room temperature.

中文翻译：

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DH36钢典型焊接接头-60℃疲劳性能研究

随着极地地区的不断发展，结构的低温疲劳性能越来越受到研究人员的关注。本研究旨在研究 T 型焊接和十字形焊接接头在 -60 °C 下的疲劳性能。在 -60 °C 下获得了基于 T 型焊接和十字形焊接接头在 50% 和 95% 置信水平下的热点应力的对数 S-N 曲线。试验结果表明，在-60℃时，T型焊接接头的疲劳性能比十字形焊接接头的疲劳性能提高近2-7%。还研究了影响焊接接头疲劳性能的因素，如应力集中系数、显微组织、维氏硬度分布和断口形貌，试验结果表明十字形焊接接头在-60℃下的疲劳性能为57。