平面应力状态“铁素体-奥氏体-铁素体”异质接头疲劳特性

Fatigue Property under Plane Stress of F-A-F Heterogeneity Joint

摘要: 针对10Ni5CrMoV钢采用0Cr18Ni24Mo6N奥氏体焊条焊接形成的“铁素体-奥氏体-铁素体”异质接头,采用薄片试样疲劳试验研究了无加强高和带加强高两种情况下平面应力状态接头的疲劳行为,并建立了带加强高接头S-N疲劳曲线。结果表明,无加强高情况下疲劳裂纹在焊缝金属内启裂并扩展;带加强高情况下疲劳裂纹在焊趾处启裂、并近似垂直载荷方向在母材内扩展至断裂,寿命较无加强高情况大幅降低,且启裂寿命占疲劳总寿命的比例较高,达到70%—80%。

Abstract: Fatigue experiment for F-A-F heterogeneity joint of 10Ni5 Cr Mo V steel welded by 0Cr18Ni24Mo6 N weld metal with and without reinforcement were conducted,fatigue property of the joint under plane stress and the S-N curve of joint with reinforcement are obtained.Resultsindicate that fatigue crack without reinforcement occurs at the weld metal; Fatigue crack of heterogeneity joint with reinforcement occurs at weld toe and continues to propagate in base metal,which is perpendicular to load direction,the life of heterogeneity joint is lower than that of heterogeneity joint without reinforcement,the proportion of the crack initiation life to total life is 70% —80%.