The stress corrosion behavior of ADC12 Al alloy tungsten inert gas (TIG) welding joint (WJ) outside its elastic deformation range was studied using electrochemical testing methods combined with surface analysis techniques in 3.5 wt% NaCl solution at 30 °C. The results showed that, with the enlargement of imparted stress, the corrosion potential of the TIG WJ shifted positively, the corrosion current density increased, and the polarization resistance decreased, indicating that the corrosion rate of the TIG WJ increased with the enlargement of imparted stress. With the prolongation of immersion time, the corrosion rate of the TIG WJ increased and then subsequently decreased. In addition, the plasticity and ductility of the TIG WJ decreased with the enlargement of imparted stress. When the imparted stress was 2100 N and 4200 N, the corrosion products on its surface were mainly composed of AlO and Al(OH). This study provided a theoretical basis for the selection of structural materials and welding methods in the automotive, marine and aerospace fields.

中文翻译：

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ADC12 铝合金钨极惰性气体保护焊接头在 3.5 wt% NaCl 溶液中的应力腐蚀效应

采用电化学测试方法结合表面分析技术，研究了 ADC12 铝合金钨极惰性气体 (TIG) 焊接头 (WJ) 在 30 ℃ 3.5 wt% NaCl 溶液中超出弹性变形范围的应力腐蚀行为。结果表明，随着外加应力的增大，TIG WJ的腐蚀电位正移，腐蚀电流密度增大，极化电阻下降，表明TIG WJ的腐蚀速率随着外加应力的增大而增大。 。随着浸泡时间的延长，TIG WJ的腐蚀速率先增大后减小。此外，TIG WJ的塑性和延展性随着外加应力的增大而降低。当施加应力为2100 N和4200 N时，其表面腐蚀产物主要由Al2O和Al(OH)组成。该研究为汽车、船舶和航空航天领域结构材料和焊接方法的选择提供了理论依据。