二重露光法による残留応力測定における板厚の影響

抄録

In this paper, we considered what the specimen thickness and measurement conditions should be in residual stress measurement using the double exposure method. Two plate specimens with thicknesses of 3.0 and 1.7 mm were cut off from a welded specimen with a thickness of 5 mm. The residual stresses of these specimens were measured using the double exposure method, and residual stress maps were created. Comparing the residual stress maps, it was found that a plate thickness in the range of 2 to 3 mm was sufficient, as the residual stress characteristics were maintained between the two specimens. In addition, for efficient measurement, it is preferable to prepare two specimens with a plate thickness of 2 or 3 mm and compare the residual stress maps to understand the macroscopic residual stress distribution and the state of microscopic residual stress. It is also advisable to measure a wide area efficiently with as high-energy X-rays as possible and high spatial resolution. Each microscopic residual stress has its own unique location and diffraction pattern. Therefore, to create a residual stress map for a thick plate by stacking multiple plates, the diffraction patterns are multiplied by an attenuation factor and then superimposed. The diffraction angle is determined using the crosscorrelation algorithm, and then the residual stress map of the stacking plate specimen can be obtained.