超声脉冲相位热成像技术是利用超声能量激励被检测材料, 如果材料中有表面或是亚表面的缺陷(裂纹或分层), 超声能量就会引起缺陷处摩擦生热或是产生热弹效应, 从而实现对缺陷部位选择性热激励。同时采用现代红外成像技术, 通过热像仪在计算机控制下进行时序热波信号探测和数据采集, 并将采集到的原始热图序列做傅里叶变换处理得到相位热图序列, 从而可定量获取材料内部缺陷的振幅及相位信息。利用这种技术对两个不同焊接能量的不锈钢激光焊缝试件以及某型号电锯锯齿轮试件进行检测, 并以图像形式直观显示了焊缝及缺陷的振幅和相位信息。

Utrasonic burst phase thermography technology used the ultrasonic as heat source to heat the material , if there are some defects(crack or delaminition) in the sample, the ultrasonic energy will cause the fiction or thermal elastic effect of the place where the defects is. At the meantime, an infrared camera controlled by the computer are used to detect the thermal wave sequences and collect the information. Then processing the original thermal sequence by Fourier transforrmation, the amplitude and phase information of the defects in the material are obtained. In this paper, two laser welded seams which are welded by different laser powers and a wheel of an electronic motor saw were detected by this method, and the amplitude and phase information was shown as images.