Effect of compression overload on fatigue strength ofwelded joint improved by compression residual stress

为了提高焊接接头的疲劳强度，常采用锤击法在焊趾处引入残余应力。然而，如果在喷丸后承受压缩过载，则焊趾处的残余压应力将使拉应力区域移动。因此，焊趾处残余压应力提高的疲劳强度在压缩超载后会降低。本研究借由平板弯曲式疲劳试验，阐明压缩超载对残余压应力提高疲劳强度的影响。

For improving the fatigue strength of welded joints, introducing the residual stress at weld toe by peening is often used. If a compression overload is subjected after peening, however, the residual compressive stress at weld toe will shift the tensile stress region. Therefore, the improved fatigue strength by residual compression stress at weld toe will be reduced after the compression overloaded. In this research, the effect of compression overload on fatigue strength improved by residual compression stress was clarified by the plate bending type of fatigue tests.