移动扫描激光线源检测圆柱表面缺陷实验研究

为了研究瑞利波与圆柱表面缺陷的相互作用,并以此作为检测圆柱表面缺陷的理论依据,设计了一套实验装置,该装置采用脉冲激光线源产生超声波,激光干涉仪探测瑞利波信号,通过改变激发源与人工缺陷的相互位置研究了瑞利波与缺陷的相互作用过程。实验中在不同的相互位置得出了不同的瑞利波波形,反射瑞利波的峰-峰值随激光源与缺陷的距离减小而增大,且当激发点位于缺陷边缘处时波形的极性改变。结果表明,当应用本装置时,通过改变人工缺陷与激光光源相对位置,再利用检测峰-峰值的极大值情况和根据接收到的瑞利波的极性可以判断缺陷的位置。

Experimental Study of the Surface Notches Detection on Cylinder

Rayleigh waves on the surface of a cylinder are detected by a laser interferometer with applying a pulse laser to generate the signal. By changing the relative position between generation source and the notch，interaction between the notch and Rayleigh waves is investigated. Experimental results demonstrate that peak-to-peak value increases with the decrease of laser source-notch distance, and that the waves’ polarity transforms. Detecting the maximum of peak-peak value can be utilized to judge the position of the notch by rotating the sample while keeping the position of generation source unchanged; the polarity can also be used in further judgments.