用激光散斑法检测金属材料的焊接缺陷

用激光散斑法对金属材料焊接进行照相，得到在某一温度区间的双曝光位移散斑图，然后逐点分析焊接部位附近的热位移场，进行求出热应变，热应力的分布，通过实例检测出焊缝中某些部位的缺陷。

The measurement of metal material welding flaws by method of laser speckle

Through the pictures taken by means of laser speckle on the metal material weldment,we can obtain double exposed displacement patterns at a temperature range.By point to point analysis heat displacement field at the welding points can be measured,and the distribution of thermal strain and thermal stress can be obtained.As a result,the flaws at welding points can be measured through experiments.