不同应力比条件下7075-T651铝合金裂纹扩展行为

Crack propagation behavior of 7075-T651 aluminum alloy under different stress ratios

摘要: 基于ASTM E647标准，对7075-T651铝合金在不同应力比下的裂纹扩展行为进行研究。采用Paris模型、Walker模型和Forman模型对裂纹扩展速率进行拟合，对比分析了各模型在不同应力比条件下的适用性和精确度。结果表明：不同应力比显著影响材料的裂纹扩展门槛值，且在应力比为−1，0.1时，门槛值接近，揭示了相似的抗裂纹扩展性能。

Abstract: Based on ASTM E647 standard, the crack propagation behavior of 7075-T651 aluminum alloy under different stress ratios was studied. The Paris model, Walker model and Forman model were used to fit the crack growth rate, and the applicability and accuracy of each model under different stress ratios were compared and analyzed. The results show that different stress ratios significantly affected the crack propagation threshold of the material, and the threshold values were close when the stress ratios were −1 and 0.1, revealing similar crack propagation resistance.