TC4-DT钛合金电子束焊接接头疲劳断裂过程的原位观测  

In-stiu Observation of Fatigue Fracture Course of TC4-DT Electron Beam Welded Joints

作　　者：金宜振[1,2] 温家伶[1] 刘昕[2] 常明[1] 

机构地区：[1]武汉理工大学材料科学与工程学院,湖北武汉430070 [2]北京航空制造工程研究所高能束流加工技术国防科技重点实验室,北京100024

出　　处：《热加工工艺》2012年第19期11-13,共3页Hot Working Technology

摘　　要：通过对TC4-DT钛合金焊接接头显微组织的观察和疲劳断裂过程的原位观测,分析了焊接接头的显微组织特征,研究了焊接接头的疲劳裂纹萌生与扩展行为。结果表明:TC4-DT焊接接头疲劳断裂于母材区,疲劳裂纹萌生于试样的边缘,裂纹既可以沿着初生α相扩展又能直接切过初生α相扩展,裂纹的萌生寿命占整个疲劳寿命的比例较大,裂纹的扩展寿命很短。By the microstructure observation and the in-stiu observation of the fatigue fracture course of TC4-DT titanium alloy welded joints, the microstructure characteristic of the welded joints was analyzed. The behavior of fatigue crack initiation and propagation was investigated. The results show that the welded joint fractures in base metal. The fatigue crack initiates at the edge of the specimen. The crack is propagated either along the primary α phase or directly through the primary α phase. The crack initiation life takes a large proportion of total fatigue life, and the crack propagation life is very short

关 键 词：TC4-DT钛合金 电子束焊接 疲劳断裂 原位观测 

分 类 号：TG405[金属学及工艺—焊接]