Fatigue Crack Width Detection Based on the Active Sensing Method: A Feasibility Study
Fatigue Crack Width Detection Based on the Active Sensing Method: A Feasibility Study
复制标题
DOI：
10.1109/icnsc.2019.8743163
复制
发表时间：
2019-05
期刊：
影响因子：
--
通讯作者：
Ning Li;Xuemin Chen;G. Song
中科院分区：
文献类型：
--
作者：
Ning Li;Xuemin Chen;G. Song
在多个行业中，金属疲劳损伤是最常见的失效类型之一，如果不能及时发现疲劳损伤，将会造成巨大的损失。为了预测金属结构在实际使用状态下的疲劳寿命，需要对金属材料进行疲劳试验。目前的疲劳试验只关注疲劳失效前的总循环次数；然而，对裂纹的发生和扩展速度的研究却很少。因此，本文基于主动感知方法，对标准金属试样在疲劳试验过程中进行裂纹扩展检测进行了可行性研究。两个PZT贴片在试样的裂纹两侧粘结，这是由循环拉压载荷引起的。一块作为致动器，另一块作为传感器。基于小波包信号能量，提出了一种损伤指标来量化接收到的信号，进而表示裂缝宽度的程度。实验结果表明，接收信号小波包能量随裂纹宽度的增大而单调减小，验证了该方法的有效性。
Across multiple industries, metal fatigue damage is one of the most common failure types, and it will induce great loss if the fatigue damage cannot be detected in a timely manner. To predict the fatigue life of metal structures under practical service status, the fatigue test of metal materials is necessary. Current fatigue tests only focus on the total number of cycles before fatigue failure; however, the occurrence and expansion speed of cracks have not been studied before. Therefore, in this paper, based on the active sensing method, a feasibility study is developed to make crack growth detection of standard metal specimen during the fatigue testing. Two PZT patches are bonded on both sides of the crack on a specimen, which is caused by cyclic tension-compression loads. One patch works as the actuator, and the other one is used as the sensor. Based on the wavelet packet signal energy, a damage index is proposed to quantify the received signals and then represent the degree of crack width. The experimental results demonstrate that the received signal wavelet package energy decreases monotonically with enlarging crack width, and thus the effectiveness of the proposed method is verified.