橡胶夹布膜片损伤声发射信号的小波识别

橡胶夹布膜片在安装过程中,因材料性能和安装因素,都会导致膜片的内部损伤,包括内部纤维的断裂、橡胶的剪切破坏。利用刀片在钢板上的摩擦来模拟密封过程中的部件摩擦,用刀片划割橡胶膜片导致膜片纤维断裂和膜片剪切破坏来模拟在膜片安装过程中橡胶膜片的损伤。通过声发射检测获得了两种情况下的声发射典型信号,并利用小波变换,对信号进行了时频域分析。结果表明这两种情况下的声发射信号在特定的连续小波变换下,在频率分布、能量分布、持续时间等方面具有明显的不同特征,可以利用这些特征对含纤维橡胶膜片在安装和使用过程中的损伤模式进行识别。

Wavelet Transform Processing for AE Signals of Fiber-Rubber Diaphragm Failure

Both breakage of the fiber enchased and shearing damage of rubber can cause failure of a fiber-rubber diaphragm during its assembling.In this research,two simple methods were used to simulate respectively the signals of diaphragm failuring and the background noise generated by frictions of components,by cutting the fiber-rubber diaphragm with a knife on a steel plate and by rubbing the steel plate directly with the knife.Acoustic emission(AE) so got was used to discriminate the two kinds of signal in order to discriminate the two different kinds of failure.The proposed time-frequency method of wavelet transformation was used to process the AE signals.After the wavelet transformation was made,there are distinct characteristics of differences between the signals of the fiber breakage and the friction,such as that of distribution of frequency,energy and duration.It is shown that wavelet transformation of AE signals was a powerful method to discriminate the failure modes of fiber-rubber diaphragm materials.