応力発光粉体を用いた試験片の応力分布の可視化に関する研究

抄録

There are many defects found in a non-destructive inspection at areas of stress concentration like a corners of the welded materials and so on. However, the mainstreams of the inspection are ultrasonic inspection, radiographic testing and magnetic particle testing, and they need an ability to find crack, defect and so on. Therefore, we will develop technology for non-destructive inspection using mechanoluminescence materials as a simple method to find internal defects. In this study, SrAl₂O₄:Eu is used as mechanoluminescence materials. Mechanoluminescence materials is phosphorescent strontium aluminate doped with europium and shows luminescence against mechanical force. It is considered that it is possible to identify the positions of the defects from the luminance distribution of light emission. We coat the mechanoluminescence materials on the test piece which with a notch and an elliptical void. As a result of performing a tensile test on the test piece coated with the mechanoluminescence materials, a peak of luminance was confirmed at the stress concentration portion. Comparing the obtained luminance distribution with the maximum principal stress distribution can be said to have the same tendency. It is thought that mechanoluminescence materials can identify the position of the defect by visualizing the stress distribution.