应力时效对DZ125镍基合金组织演化及蠕变抗力的影响  

Effect of stress aging on microstructure evolution and creep resistance of DZ125 nickel-based superalloy

作　　者：田宁 田素贵 张宝帅[2] 于慧臣[3] 李秋阳[2] TIAN Ning;TIAN Su-gui;ZHANG Bao-shuai;YU Hui-chen;LI Qiu-yang(School of Mechanical Engineering, Guizhou University of Engineering Science, Bijie 551700, China;School of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110870, China;Aviation Key Laboratory of Science and Technology on Materials Testing and Evaluation, Science and Technology on Advanced High Temperature Structural Materials Laboratory, Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation, AVIC Beijing Institute of Aeronautical Materials, Beijing 100095, China)

机构地区：[1]贵州工程应用技术学院机械工程学院,毕节551700 [2]沈阳工业大学材料科学与工程学院,沈阳110870 [3]中航工业北京航空材料研究院材料检测与评价航空科技重点实验室国防科技重点实验室航空材料检测与评价北京市重点实验室,北京100095

出　　处：《中国有色金属学报》2018年第3期536-546,共11页The Chinese Journal of Nonferrous Metals

基　　金：贵州省普通高等学校创新团队项目(黔教合人才团队字[2015]73);贵州省科技合作计划项目(黔科合LH字[2015]7583)~~

摘　　要：通过蠕变性能测试,组织结构观察和晶格常数测定,研究应力时效对DZ125镍基合金组织演化与蠕变抗力的影响。结果表明:合金在980℃、90MPa近服役条件下的蠕变寿命是9714h;蠕变期间,样品中间区域的γ′相优先形成完整的筏状组织,在无应力的肩部区域,γ′相呈现串状形态;随应力时效时间延长至9714h,合金中筏状γ′相的厚度尺寸从0.4μm增加至1.8μm,合金中γ′、γ两相的晶格常数值增加,两相的错配度增大。其中,应力时效致使筏状γ′相粗化及错配度增大,可改善蠕变抗力,是合金在近服役条件具有较长蠕变寿命的原因之一。By means of creep properties measurement, microstructure observation and parameters measurement, the effects of the stress aging on microstructure evolution and creep resistance of DZ125 nickel-based superalloy were investigated. The results show that the creep life of the alloy at 980℃ and 90 MPa near service condition is 9714h. During creep, the various morphologies of γ′ and γ phases display in different regions of sample. Wherein, the γ′ phase in the middle region of sample firstly transforms into rafted structure, while the γ′ phase in the stress-free region exhibits bunch-like structure. As the time of the stress aging prolongs to 9714h, the size of the rafted γ′ phase in thickness increases from 0.4μm to 1.8μm, which increases the parameters and misfits of γ′ and γ phases in the alloy. The deformation mechanisms of alloy during steady state creep are dislocations slipping in the matrix channels and climbing over the rafted γ′ phase. In the later stage of creep, the deformation mechanisms of alloy are dislocations shearing into the rafted γ′ phase. Wherein, the fact that the stress aging results in the coarsening of γ′/γ′ phases to increase the misfits may improve the creep resistance of the alloy, which is thought to be one of the reasons of the alloy with a longer creep lifetime.

关 键 词：DZ125镍基合金 应力时效 蠕变 γ′相粗化 γ′/γ晶格错配度 变形特征 

分 类 号：TG146.1[一般工业技术—材料科学与工程]