DD8单晶镍基高温合金热机械疲劳后γ/γ'界面位错网产生内应力的计算  

CALCULATION OF THE INTERNAL STRESSES AT THE γ/γ' INTERFACE OF DD8 SINGLE CRYSTAL NICKEL BASE SUPERALLOY AFTER THERMO-MECHANICAL FATIGUE

作　　者：周丽[1] 李守新[1] 王跃臣[1] 王中光[1] 

机构地区：[1]中国科学院金属研究所沈阳材料科学国家(联合)实验室

出　　处：《金属学报》2005年第3期245-250,共6页Acta Metallurgica Sinica

基　　金：国家重点基础研究发展规划资助项目G19990650

摘　　要：计算了DD8单晶镍基高温合金在同相(IP)和反相(OP)热机械疲劳(TMF)后γ／γ'相界面上产生的位错网的内 应力.结果表明:IP TMF条件下, γ／γ'相界面上产生的位错网可以释放掉大部分错配应力,同时因位错网的存在导致了γ' 沉淀相发生了明显的筏化现象. OP条件下产生的层错未造成基体内应力分布的不同,因此未发生γ'沉淀相的筏化.The internal stresses produced by dislocation networks at the γ/γ' interfaces in a single crystal nickel-base superalloy DD8 has been studied after in phase (IP) and out of phase (OP) thermo-mechanical fatigue (TMF) testing. The results indicate that one of the roles of the dislocation networks at the γ/γ' interfaces is to relax most of the misfit stress under IP TMF, on the other hand, the existence of the dislocation networks results in the directional coarsening of the γ' precipitates. While under the OP TMF, the internal stress in the matrix induced by stacking faults does not vary significantly, the γ' precipitates do not show direction coarsening in OP test.

关 键 词：单晶镍基高温合金 热机械疲劳 位错网 γ/γ′界面 内应力 

分 类 号：TG132.3[一般工业技术—材料科学与工程] TG113.25[金属学及工艺—合金]