超音波加振を付加したステンレス鋼ブロック材の溶接残留応力評価

抄録

Welding is used in many structures. Since heat is applied locally to the material in welding, tensile residual stress is generated near the bead, causes the stress corrosion cracking in stainless steel. We have developed welding residual stress reduction for structural rolled steel using ultrasonic vibration load. In this study, we apply this method for stainless steel SUS304 block material, and measure welding residual stress. Comparing the results of residual stress measurement between with and without ultrasonic vibration load, effectiveness of this method on stainless steel is investigated. As a result, this method can reduce welding residual stress in stainless steel. The reduction rate in case with acceleration amplitude of 5000m/s² is greater than one in case with acceleration amplitude of 2000m/s². From the t-test results, significant differences of welding residual stress reduction between them were confirmed. In case of ultrasonic vibration load with acceleration amplitude of 2000m/s², welding residual stress was reduced 16% compared to no load. In case of 5000m/s², it was reduced to 30%.