损伤容限型TC4-DT合金疲劳裂纹扩展行为研究  

Fatigue Crack Growth Behavior of TC4-DT Alloy in Damage Tolerance Type

作　　者：李辉[1] 赵永庆[1] 曲恒磊[1] 曾卫东[2] 

机构地区：[1]西北有色金属研究院,陕西西安710016 [2]西北工业大学,陕西西安710072

出　　处：《稀有金属材料与工程》2007年第6期963-967,共5页Rare Metal Materials and Engineering

基　　金：国家"863"项目(2002AA305107)资助

摘　　要：利用OM(光学金相)、SEM对损伤容限TC4-DT合金双态组织中的疲劳裂纹扩展行为进行研究。结果表明:裂纹扩展遇到初生α相时,既能以绕过初生α相的方式扩展,又能直接切过初生α相向前扩展;预裂区和快速扩展区主要是以微区解理断裂为主,稳态扩展区主要是以疲劳条带扩展机制为主,同时也存在微区解理断裂机制。The fatigue crack growth characters and fracture mechanism in damage tolerance type were studied for the TC4-DT alloy plate of 30 mm in thickness by rolling in α＋β phase region using MTS-8 l0 low cycle fatigue mechanism after heat-treatment. The results show that the fatigue crack spreaded not only round the primary a but also ahead directly spliting it. The cracks in the fore-crack region and the fast growth region were mainly in the form of micro-cleavage fracture; and spreaded in the form of strip mechanism in the stable spread region with some behaviors of micro-cleavage fracture.

关 键 词：TC4-DT 钛合金 双态组织 裂纹扩展 

分 类 号：TG115.57[金属学及工艺—物理冶金]