腐蚀损伤对AA7075-T651铝合金疲劳行为影响的研究  

Effect of Corrosion Damage on Fatigue Behavior of AA7075-T651 Al-alloy

作　　者：翁硕 俞俊 赵礼辉[1,2,3] 冯金芝 郑松林[1,2,3] WENG Shuo;YU Jun;ZHAO Lihui;FENG Jinzhi;ZHENG Songlin(School of Mechanical Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China;Key Laboratory of Strength and Reliability Evaluation of Auto Mechanical Components for Mechanical Industry,Shanghai 200093,China;Shanghai Public Technology Platform for Reliability Evaluation of New Energy Vehicles,Shanghai 200093,China)

机构地区：[1]上海理工大学机械工程学院,上海200093 [2]机械工业汽车机械零部件强度与可靠性评价重点实验室,上海200093 [3]上海市新能源汽车可靠性评价公共技术平台,上海200093

出　　处：《中国腐蚀与防护学报》2022年第3期486-492,共7页Journal of Chinese Society For Corrosion and Protection

基　　金：国家自然科学基金(52005336);中国博士后基金面上项目(2020M671167);上海市科委“扬帆计划”(19YF1434400)。

摘　　要：为研究腐蚀损伤对AA7075-T651铝合金疲劳行为的影响,首先分别将AA7075-T651铝合金试样浸泡在3.5%(质量分数) NaCl溶液中150和500 h,然后,使用含腐蚀损伤试样进行疲劳试验,获得含不同腐蚀损伤特征试样的疲劳寿命分布特征。结果表明,与原始试样的疲劳寿命相比,相同载荷条件下腐蚀损伤会明显地降低铝合金的疲劳寿命,但是,尽管浸泡500 h试样的腐蚀损伤特征尺寸明显大于浸泡150 h的,两者的疲劳寿命差异却并不明显。针对腐蚀损伤特征与疲劳寿命的关系,本文采用缺口系数相关的Stromeyer三参数S-N预测模型,对含腐蚀损伤铝合金试样的疲劳寿命进行了预测分析,实验结果基本分布在预测结果的二倍分散带内,有效地验证了该寿命预测方法的准确性。The fatigue test for the 7075-T651 Al-alloy samples with and without being immersed in3.5%(mass fraction) NaCl solution for 150 and 500 h, respectively, was carried out, in order to reveal the influence of corrosion damage on the fatigue behavior of the alloy. The results show that compared to the blank alloy samples, the fatigue life of 7075-T651 Al-alloy subjected to immersion corrosion is significantly reduced due to the presence of corrosion damage. The size of corrosion pits in the specimens immersed for 500 h are much large than those for 150 h, but the fatigue life of the two types of specimens with corrosion damage are more or less at the same stress level. Based on the fatigue notch coefficient theory and Stromeyer three-parameter S-N curve formula, the life of the damaged Al-alloy sample was predicted, and the predicted results totally located in the double dispersion band, which indicates that the predicted formula fits well with the results of experimental results.

关 键 词：腐蚀损伤 疲劳寿命 AA7075-T651铝合金 

分 类 号：TG146.2[一般工业技术—材料科学与工程]