试验分析振动信号与残余应力的关系

Analysis of the Relationship Between Vibration Signal and Residual Stress by Experiment

通过采集焊接钢板的振动信号,对其进行CEEMD分解,分解后通过相关系数筛选出有用分量,并对其进行小波降噪。最后对降噪的固有模态分量进行希尔伯特边际谱分析,得到其固有频率以及固有频率所对应的幅值,探究其与残余应力大小之间的一般性规律。并把有残余应力和消除残余应力的焊接件作对比试验,得出如下结论:(1)残余应力的存在会导致焊接件固有频率增大;(2)与尺寸小的焊接件相比,大尺寸的焊接件固有频率受残余应力的影响小;(3)高阶固有频率比低阶固有频率更容易受残余应力影响;(4)当焊接件存在残余应力时,固有频率所对应的幅值比消除残余应力时大。

By collecting the vibration signal of the welded steel plate, it is decomposed by CEEMD, the useful componentsare screened by correlation coefficient after decomposing, and wavelet noise reduction is performed. Finally, the Hilbert marginal spectrum analysis is carried out on denoisingIMF, the natural frequency and its amplitude are obtained,exploring the general rules between it and the residual stress, making the welding parts with residual stress and the relaxation one are compared and tested. The conclusionsare as follows:(1) The existence of residual stress will lead to an increase in natural frequency;(2) A welded part with a small size is more affected by residual stress than a largerone on natural frequency;The high-order natural frequency is more susceptible than the low one in residual stress;(4) the natural frequency corresponds to a larger amplitude than when there is no residual stress.