声发射模拟信号在水介质中传播的波形特征

The Waveform Characteristic of Acoustic Emission Simulation Signals Propagation in Aqueous Medium

采用全波形声发射仪测量了声波发生器产生的,并分别经钢板和水介质传播的声发射模拟信号,对其波形特征进行了时域分析、频谱分析和对比研究。结果表明,AE模拟信号经水介质传播后的幅度较经钢板传播后明显降低;AE模拟信号通过水介质没有明显的频散现象发生,而通过钢板传播后频散现象明显,这与钢板表面和材料内部的晶界有关。

The AE simulation signals, which were produced by a sound wave generator and propagating in the steel plate and aqueous medium respectively, were detected by a full waveform acoustic emission detector, and the waveform characteristic was studied comparatively with the help of time domain analysis and frequency spectrum analysis. The results showed that the amplitudes of the AE simulation signals propagating in the aqueous medium were much more lower than those propagating in the steel plate. The dispersion phenomenon of the AE simulation signals propagating in the aqueous medium was not obvious, but was obvious when propagating in the steel plate due possibly to its surface and crystal boundary.