30CrMnSiNi2A超高强度钢电子束焊接接头的疲劳性能  

Fatigue Property of Electron Beam Welding Joint of 30CrMnSiNi2A Ultra High Strength Steel

作　　者：陈素明[1] 张兵宪[1] 张颖 CHEN Suming;ZHANG Bingxian;ZHANG Ying(AVIC Xi'an Aviation Industry Group Corporation Limited,Xi'an 710089,China)

机构地区：[1]航空工业西安飞机工业(集团)有限责任公司

出　　处：《热加工工艺》2019年第21期35-38,43,共5页Hot Working Technology

摘　　要：对7.5 mm+10.5 mm超高强度钢30CrMnSiNi2A真空电子束锁底焊接接头和母材进行了疲劳性能的研究。分析接头疲劳性能数据,拟合中值疲劳S-N曲线,对比分析接头与母材的疲劳性能,并采用扫描电镜观察进行断口分析,获取焊接件和母材的疲劳失效机理。结果表明,在低应力区,母材裂纹萌生形式以角裂纹源为主,焊接件裂纹萌生形式以气孔裂纹源为主。在高应力区,疲劳寿命在3×10^4~1×10^5,母材和焊接件疲劳性能相当。母材的疲劳极限为1102MPa,焊接件的疲劳极限为980 MPa。The fatigue property of vacuum electron beam bottom-locked welded joint of 7.5 mm+10.5 mm ultra-high strength steel 30CrMnSiNi2A and the base metal was studied, and the data of fatigue property of joint was analyzed and the median S-N curve of both the joint and base metal was fitted to compare their fatigue property. The fracture was analyzed by SEM observation and the fatigue failure mechanism of welded specimen and base metal was obtained. The results indicate in low stress zone, the fatigue crack of the base metal mainly initiates at the corner and the fatigue crack of welded specimen mainly initiates at the air hole. And in high stress zone, the fatigue life is in 3 ×10^4-1×10^5, and the fatigue properties of base metal and welded part are equivalent. The fatigue limit of the base metal is 1102 MPa, the fatigue limit of the welded specimen is 980 MPa.

关 键 词：电子束焊接 30CrMnSiNi2A超高强度钢 疲劳极限 疲劳寿命 

分 类 号：TG456.3[金属学及工艺—焊接]