不同小波基在碳钢材料声发射信号分析中的应用

Application of different wavelet bases in acoustic emission signal for carbon steel material

为研究不同小波基对同一声发射信号分析结果之间的可比性,以碳钢在塑性变形和裂纹扩展时产生的声发射信号为研究对象,用db5和sym5两种常用小波基对检测信号进行了分析对比。结果表明,对碳钢在塑性变形和裂纹扩展时产生声发射信号,2种小波变换在信号能量分布趋势上分析结果一致,在主要信号峰值对应频率上分析结果接近,平均相对偏差仅为1.53%,而在各级信号占能量比例的具体值和信号峰值上偏差较大,平均相对偏差在10%左右,可比性较差。

In order to investigate the comparability between acoustic emission signals using different wavelet bases, analyses of the acoustic emission signals during plastic deformation and crack propagation in carbon steel have been done using two usual db5 and sym5 wavelet bases. Results show that the trends of signal energy distribution are coincident for two wavelet transforms. Major signal peak frequencies are very close and the average relative divergence is only 1.53%. But there are significant differences in energy ratios and signal peak values of various level signals and the average relative divergence is about 10% , which means the comparability is poor.