本文运用线弹性断裂力学理论,用表面裂纹法,研究了LD10CS铝合金板材及其焊接接头的断裂韧性和裂纹尺寸对断裂应力的影响,并分析了焊接接头低韧性部位的断口特征。结合箱体实际,分析讨论了断裂韧性参数的应用。 In this paper, using the theory of linear elastic fracture mechanics, the effect of fracture toughness and crack size of LD10CS aluminum alloy sheet and its welded joints on the fracture stress was investigated by surface crack method. The fracture characteristics of the low toughness parts of the welded joints were analyzed. Combined with the actual case, analysis and discussion of fracture toughness parameters.