30CrMnSiNi2A钢电子束焊接头的疲劳裂纹扩展特性研究  

Study on Fatigue Crack Propagation Characteristics of Electron Beam Welded Joint of 30CrMnSiNi2A Steel

作　　者：张颖云 胡生双 朱增辉 郑超 龙健 张林杰[2] ZHANG Yingyun;HU Shengshuang;ZHU Zenghui;ZHENG Chao;LONG Jian;ZHANG Linjie(AVIC Xi’an Aircraft Industry Group Company Ltd.,Xi’an 710089,China;State Key Laboratory for Mechanical Behavior of Materials,Xi’an Jiaotong University,Xi’an 710049,China)

机构地区：[1]中航西安飞机工业集团股份有限公司,西安710089 [2]西安交通大学金属材料强度国家重点实验室,西安710049

出　　处：《航空制造技术》2022年第8期113-118,共6页Aeronautical Manufacturing Technology

摘　　要：比较了26mm厚30CrMnSiNi2A超高强度钢电子束焊接头的母材、热影响区和焊缝区的疲劳裂纹扩展速率。试验结果表明,母材的抗疲劳裂纹扩展性能最好;热影响区抗疲劳裂纹扩展性能相对较弱;焊缝区的抗疲劳裂纹扩展性能接近母材。分别观察了母材、热影响区和焊缝区3个区域疲劳试样的断口形貌,发现接头各区域均呈现多源启裂特征,在稳定扩展区域和快速扩展区域均发现疲劳条纹。在接头3个区域最后失稳断裂区域均发现大量韧窝,呈现韧性断裂特征。通过光镜和扫描电镜观察了接头3个区域的显微组织特征,发现接头各区域在光镜和扫描电镜下的显微组织差异较小,均为回火马氏体。This paper compared the fatigue crack growth rate of the base metal(BM),heat affect zone(HAZ)and weld metal(WM)of the ultra-high strength steel electron beam welded joint of 26mm thick 30CrMnSiNi2A.The experimental results showed that the fatigue crack growth resistance of the BM was the best;HAZ was relatively weak;WM was closed to that of the BM.The fractured morphologies of BM,HAZ and WM fatigue samples were observed.It was found that multi-source crack initiation was found in each region of the joint,fatigue striations were found in the stable and fast crack propagation area,and a large number of dimples were found in fractured zone of the three regions of the joint,presented ductile fracture characteristics.The microstructure characteristics of the three regions of the joint were observed by optical microscope and scanning electron microscope.It was found that the differences between the microstructure of each region of the joint were slightly,and all of them were tempered martensite.

关 键 词：超高强度钢 电子束焊接 疲劳裂纹扩展速率 疲劳断口形貌 疲劳条纹 

分 类 号：V262[航空宇航科学与技术—航空宇航制造工程]