用激光散斑法检测金属材料的焊接缺陷

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

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

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.