Mo和Re对含Ru新型单晶高温合金组织稳定性的影响  

Effects of Mo and Re on the Microstructural Stability of a Novel Single Crystal Superalloys Containing Ru

作　　者：崔金艳 张建庭 尧健 王冲 郭建政 Cui Jinyan;Zhang Jianting;Yao Jian;Wang Chong;Guo Jianzheng(Shenzhen Wedge Central South Research Institute Co.,Ltd,Shenzhen 518000,China;State Key Laboratory of Powder Metallurgy,Central South University,Changsha 410083,China)

机构地区：[1]深圳市万泽中南研究院有限公司,广东深圳518000 [2]中南大学粉末冶金国家重点实验室,湖南长沙410083

出　　处：《稀有金属材料与工程》2023年第4期1490-1498,共9页Rare Metal Materials and Engineering

基　　金：深圳市科技创新委员会项目(20150128085205453)。

摘　　要：制备名义成分分别含0.4%Mo-6.4%Re、2.8%Mo-6.4%Re和0.4%Mo-6.7%Re的3种新型镍基单晶高温合金。分析合金经过热处理后的元素分配配比,经过1100℃,0~1000 h的热暴露后的γ′相演化、拓扑密排相(TCP)析出规律。结果表明,Re含量的微量增加和Mo含量的大幅增加会明显增加各元素在枝晶干和枝晶间、γ/γ′两相间的偏聚,低扩散元素Re等在枝晶干和γ相的偏析降低了热暴露过程中γ′相的粗化速率。Re的微量增加,促进P相析出数量增多,但P相的长大受到一定限制,原因是Re促进P相形成元素Re、W和Ru在枝晶干的偏聚,促进P相形核,使P相数量增多,但大量析出的P相互相接触交叉,反而降低了长大速率。Mo含量的大幅增加,使得在1100℃长时热暴露过程中同时存在μ相和P相,且μ相优先析出,数量多,尺寸大,而P相析出时间延迟,数量少,尺寸小,原因是Mo促进μ相的主要组成元素Re、W、Mo在枝晶干的偏聚,尤其是Mo含量的提高,促进μ相优先析出,随着μ相形成元素的消耗,以及P相在1100℃下更稳定,促使P相在μ相之后析出。Three novel nickel-based single crystal superalloys containing 0.4%Mo-6.4%Re,2.8%Mo-6.4%Re and 0.4%Mo-6.7%Re,in nominal composition were prepared.The element concentrations of alloys after SHT(standard heat treatment)were measured,γ′phase evolution and topological close-packed phase(TCP)precipitation of the alloys thermal exposed at 1100℃up to 1000 h were analyzed.The slight increment of Re and the increase of Mo content obviously facilitate the segregation of elements between dendrite and interdendrite,and betweenγandγ′phase.The coarsening rate of theγ′phase during thermal exposure reduces due to the segregation of low-diffusion elements such as Re in the dendrite core and theγphase.The slight increase of Re promotes the precipitation of P phase but inhibites the growth rate of P phase,because the nucleation of the P phase is promoted by the segregation of the P phase forming elements Re,W and Ru in the dendrite core.However,the growth rate is inhibited because of contaction and intersection of precipitated P in large amount.The large increase of Mo content makes bothμphase and P phase exist during the long-term thermal exposure at 1100℃.Theμphase preferentially precipitates with a large number and a large size,while the precipitation of the P phase is delayed with smaller number and size.Mo promotes the segregation of the main constituent elements ofμphase,Re,W,and Mo in the dendrite core,especially the increase of Mo content,which promotes the preferential precipitation ofμphase.With the consumption ofμphase forming elements,and the presence of P phase is more stable at 1100°C,P phase precipitates subsequently.

关 键 词：新型镍基单晶高温合金 热暴露 组织稳定性 P相 Μ相 

分 类 号：TG146.15[一般工业技术—材料科学与工程]