Abstract：This work was performed on 7N01 aluminum alloy which used in the body of high-speed train and damage was monitored based on acoustic emission (AE) and digital image technology during three-point bending failure of 7N01 aluminum alloy, conventional AE parameters and bispectrum analysis were used to study the characteristic of AE signals during the crack initiation and unstable propagation of 7N01 aluminum alloy. The result shows that AE energy and centroid frequency (CF) were effective indicators to predict the crack initiation of 7N01 aluminum alloy. Bispectrum contour map of AE signals shows the coupling relationship of the two frequency components which makes it easy to identify different stages during three-point bending of 7N01 aluminum alloy. The digital images of damage evolution from monitoring the notch tip region of 7N01 sample verify the prediction of AE signals. The results indicate that AE technique provides the basis for predicting the initiation of micro-crack.
朱荣华, 刚铁, 万楚豪. 基于声发射和双谱分析的铝合金损伤原位监测研究[J]. 材料工程, 2013, 0(5): 67-72.
ZHU Rong-hua, GANG Tie, WAN Chu-hao. In-situ Damage Monitoring of Aluminum Alloy Based on Acoustic Emission and Bispectrum Analysis. Journal of Materials Engineering, 2013, 0(5): 67-72.
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