Effects of pitting corrosion on fatigue life of aluminum alloy Y12CZ based on initial discontinuity state

作     者：郁大照 陈跃良 胡家林 杨茂胜 

作者机构：Naval Aeronautical Engineering AcademyYantai 264001China Qingdao BranchNaval Aeronautical Engineering AcademyQingdao 266041China 

出 版 物：《中国有色金属学会会刊：英文版》 (Transactions of Nonferrous Metals Society of China)

年 卷 期：2006年第16卷第A3期

页      面：1319-1322页

核心收录：

学科分类：080503[工学-材料加工工程] 08[工学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：Project(50675221) supported by the National Natural Science Foundation of China 

主　　题：铝合金 疲劳分析 金属腐蚀 强度 

摘      要：Based on initial discontinuity state (IDS) of material, a preliminary analytical model was presented to evaluate the effect of interaction of pitting corrosion and fatigue loading on the residual fatigue life of aluminum alloy LY12CZ. A life prediction was carried out using constant and variable amplitude loading for various pitting corrosion levels, and the prediction agreed reasonably with the available test data. The results suggest that the combination of a pit and IDS can be treated as the initial crack size. Pitting corrosion causes a significant decrease in fatigue lives with small corrosion depths. But the effect of pit on fatigue life is gradually reduced with increasing pit size. A pit with a constant depth can be applied to the model for long exposure structure. A preliminary recommendation for the pit depth is about 1 mm for LY12CZ. At last the effect of multiple-site corrosion damage (MSCD) on fatigue life was also studied, and the result shows that MSCD can decrease substantially fatigue life compared with that of a single crack.