脉冲电流对一种镍基高温合金γ'相粗化行为的影响  

Effects of electropulsing treatment on coarsening behavior of γ′phase in a nikel base superalloy

作　　者：刘杨[1] 王磊[1] 冯飞[1] 张北江[2] 赵光普[2] 

机构地区：[1]东北大学材料各向异性与织构教育部重点实验室,沈阳110819 [2]钢铁研究总院高温材料研究所,北京100081

出　　处：《材料与冶金学报》2011年第4期288-291,295,共5页Journal of Materials and Metallurgy

基　　金：国家重点基础研究发展计划(973)项目(2010CB631203);国家自然科学基金项目(51001021);国家教育部博士点专项基金项目(20100042120008;20100042110006)

摘　　要：对一种镍基高温合金进行脉冲电流处理,研究了脉冲电流与时效处理过程中γ'相的粗化行为.结果表明,与相同温度时效状态相比,脉冲电流条件下合金中γ'相的长大速率显著增加.脉冲电流下γ'相的粗化遵循Lifshitz-Slyozov-Wagner理论,与时效过程中γ'相粗化激活能相比降低64.3%.脉冲电流处理过程中,脉冲电子流加剧合金原子自身的热振动,使原子处于相对高能状态,降低合金中原子跃迁激活能;脉冲电流初期由于瞬时升温而形成热应力,提高合金中的空位浓度,加速合金中的原子扩散,促进γ'相的粗化.A nickel base superalloy was treated by high current density electropulsing. The results show that the growth rate of γ＇ by high current density electropulsing is increased obviously compared with that by aging at the same temperature. The γ＇ coarsening kinetics by high current density electropulsing follows the LSW theory. The value of activation energy for γ＇ coarsening by electropulsing is about 64. 31% reduced compared with that by aging. Since the electropulse can accelerate the atomic thermal vibrations, make the atoms be in high energy state, the activation energy for atomic transition during the high current density electropuMng will be decreased. On the other hand, the thermal stress induced by the transient temperature rising on the early stage of electropulsing increases the vacancy concentration, accelerates the atom diffusion, and therefore promotes the coarsening of γ＇ phase.

关 键 词：脉冲电流 γ’相 高温合金 激活能 粗化行为 

分 类 号：TG146.1[一般工业技术—材料科学与工程] TG111.5[金属学及工艺—金属材料]