双向残余应力的超声检测及其对比性研究

针对航天器铝合金平面双向残余应力超声波检测进行验证性研究。分别在双向平板试件上采用应变片法,在对接焊焊接试件上采用X射线衍射法和电子散斑法进行对比性残余应力检测试验。结果表明,平板试验件上应变片法和超声法的测量结果的最大偏差小于4MPa,近似相同。由于不同深度上,焊接试验件上残余应力不同,超声法、X射线法和电子散斑法得到的焊接残余应力的数值有所差距,但是其趋势基本相同,且都符合对接焊焊板上平行于焊缝方向的残余应力的分布趋势。

Ultrasonic Detection of the Two-Way Residual Stress and Its Comparative Study

In this paper,the verification study of the ultrasonic detection for aluminum biaxial residual stress is conducted.Strain gauge method was used on the two-way flat specimen;X-ray diffractometry and electron speckle method were used for the comparative examination on the welding test specimen.The difference between measurement results by the strain gauge method and by the ultrasonic method on the flat panel test piece is less than4 MPa,which shows that the two methods shall give an approximately the same result.Meanwhile,the value of the welding residual stress obtained by the ultrasonic method,the X-ray method and the electronic speckle method is from different depths,and the residual stress on the welded test pieces are different at different depths,so the values of the three methods shall show some deviations,but the stress trends are basically the same,and are in line with the distribution trend of residual stress parallel with the weld direction of butt welding plate.