一种X80管线钢焊接接头疲劳裂纹扩展门槛值的研究  

Research of Fatigue Crack Growth Threshold on the Welded Joint of X80 Pipeline Steel

作　　者：王博[1] 张骁勇[1] 马晶[1] 张灵芝[1] 李辉辉[1] 

机构地区：[1]西安石油大学材料科学与工程学院,西安710065

出　　处：《焊管》2014年第3期9-13,共5页Welded Pipe and Tube

基　　金：国家自然科学基金项目(51174165)

摘　　要：采用疲劳试验、显微分析方法和力学性能分析等手段,对焊接热输入为20 kJ/cm的一种X80管线钢焊接接头在不同应力比条件下的疲劳裂纹门槛值进行了研究。研究结果表明,随着应力比的增加,疲劳裂纹扩展速率da/dN增大,疲劳裂纹扩展门槛值呈逐渐降低的趋势。在热输入为20 kJ/cm时,焊缝的组织以针状铁素体为主,含少量多边形铁素体,有很好的韧性。The fatigue crack growth threshold on the welded joint of X80 pipeline steel after different stress ratio, with 20 kJ/cm welding heat input, was investigated through fatigue test, microscopic analysis method and mechanical property test. The results showed that, with the stress ratio increasing, and the fatigue crack growth rate da/dN enlarging, the fatigue crack growth threshold gradually presents decrease trend. When the heat input is up to 20 kJ/cm, the microstructure of weld is mainly composed of acicular ferrite, containing a small amount of polygonal ferrite, is with good toughness.

关 键 词：X80管线钢 疲劳裂纹扩展速率 疲劳裂纹扩展门槛值 应力比 

分 类 号：TG973.3[金属学及工艺—钳工工艺]