文献类型：期刊文献

英文题名：Influence of cyclic-loading induced fatigue micro-crack growth on generation of nonlinear ultrasonic Lamb waves

作者：Ding, Taotao[1];Zhu, Wujun[1];Ma, Congyun[1];Xiang, Yanxun[1];Deng, Mingxi[2];Xuan, Fu-zhen[1]

机构：[1]East China Univ Sci & Technol, MOE Sch Mech & Power Engn, Key Lab Pressure Syst & Safety, Shanghai 200237, Peoples R China;[2]Chongqing Univ, Coll Aerosp Engn, Chongqing 400044, Peoples R China

年份：2021

卷号：40

期号：3

外文期刊名：JOURNAL OF NONDESTRUCTIVE EVALUATION

收录：;EI(收录号：20212810614897);WOS:【SCI-EXPANDED(收录号:WOS:000669296400002)】；

基金：This work was supported by the National Natural Science Foundation of China (Nos. 12025403, 12004114, U1930202, and 518353003), and the China Postdoctoral Science Foundation (No. 2020M671015).

语种：英文

外文关键词：Nonlinear Lamb waves; Fatigue damage; Third-order elastic constants; Micro-cracks

摘要：Fatigue damage and micro-cracks growth have been proved to be closely related to the nonlinear effect of ultrasonic Lamb waves propagation in materials. In this paper, the relationship among fatigue life, length and width of micro-cracks, and the acoustic nonlinearity parameter was established. The variation of the acoustic nonlinearity parameter caused by fatigue damage was analyzed based on micro-cracks growth. Considering the multimodal nature of nonlinear Lamb waves, we selected the low-frequency mode pairs S0-s0 and S1-s2 to evaluate fatigue damage in 7075 aluminum alloy plates. Both FE simulations and experiments show that the mode pair S1-s2 is more suitable than S0-s0 for the assessment of fatigue damage. It was found that with increasing fatigue cycles, the relative acoustic nonlinearity parameter A(2)/A(1)(2) firstly increases because the micro-cracks length extends while the micro-cracks width does not change much. The relative acoustic nonlinearity parameter A(2)/A(1)(2) reaches its peak at about 60% of the fatigue life. Then the relative acoustic nonlinearity parameter A(2)/A(1)(2) decreases because of the rapid increase in the micro-cracks width. Our findings clarify the mountain-shape curve between the relative acoustic nonlinearity parameter A(2)/A(1)(2) and the fatigue cycles.