The AE signal analysis of the fatigue growth test using acoustic emission

Abstract

The acoustic emission (AE) technique is a well-known non-destructive test which is widely applied in research and industry. It is mainly used in monitoring the onset of the cracking process in materials to predict and prevent the factures that attract the attention of researchers to apply condition monitoring techniques into detecting the early stage of cracks. The object of this study is to obtain the features of AE signals caused by crack growth. The envelope analysis with discrete wavelet transform (DWT) is used to find the characteristic of AE signal. To estimate the features, the crack length was divided into three parts. From the raw signals and transferred signals, the power spectrum which was processed by the envelope analysis with DWT was generated. Through this experiment, the envelope analysis with DWT is a better way to analyze the original AE signals. In this paper, the results of fatigue crack growth can contribute to a database of crack detection. ? Springer-Verlag London 2014.