A7N01铝合金退火处理后焊接接头疲劳裂纹扩展特性  

Fatigue crack propagation characteristics in A7N01 aluminum alloy welded joint after annealing treatment

作　　者：魏书波[1] 

机构地区：[1]南车青岛四方机车车辆股份有限公司,266111

出　　处：《焊接》2015年第2期59-62,72,共4页Welding & Joining

基　　金：国家高技术研究发展计划资助项目(2011AA11A101)

摘　　要：针对高速列车底架结构采用A7N01铝合金的焊接接头进行了疲劳裂纹扩展速率试验,利用扫描电镜以及光学显微镜方法,研究了母材、热影响区及焊缝微观组织的演化,晶粒中弥散强化相、粗大强化相、粗大析出相以及杂质相等第二相粒子对疲劳裂纹扩展抗力的影响,进而研究A7N01铝合金焊接接头不同区域的疲劳裂纹扩展机制,为轨道车辆的安全可靠性评估提供基础性数据。The A7N01 aluminum alloy welded joints are used in the localization of the shinkansen high speed train chassis structure.Fatigue crack growth rate test were conducted,and the microstructure evolutions in base metal,HAZ and weld were studied by using scanning electron microscope and optical microscope.The influences of phase particle including grain size of the dispersion of strengthening phase,bulky strengthening phase,bulky exhalation phase and impurity phase on fatigue crack propagation resistance were also studied.Then,the fatigue crack propagation in different regions of A7N01 aluminum alloy welded joint were investigated,which provides the basic data for the evaluation of the safety and reliability of high-speed trains.

关 键 词：疲劳裂纹 扩展速率 扩展抗力 扩展机制 

分 类 号：TG457.14[金属学及工艺—焊接]