定向凝固高温合金组织演变对持久性能的影响  

Effects of Microstructural Evolution of Directionally Solidified Superalloy on Stress Rupture Property

作　　者：崔金艳 张建庭 尧健 Cui Jinyan;Zhang Jianting;Yao Jian(Shenzhen Wedge Central South Research Institute Co.,Ltd,Shenzhen 518000,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

出　　处：《稀有金属材料与工程》2021年第7期2568-2576,共9页Rare Metal Materials and Engineering

基　　金：深圳市发展和改革委员会项目(SZDRC 20181000)。

摘　　要：对比研究了定向凝固高温合金GTD111以及自主设计合金WZ-D2的铸态、热处理态和经980℃/190 MPa持久拉伸后的γ’相、碳化物以及拓普密排(TCP)有害相析出的特征演变及其对持久性能的影响。结果表明:WZ-D2的铸态共晶尺寸和数量均显著小于GTD111;热处理态WZ-D2的γ’相面积分数明显高于GTD111,且立方度略高于后者。GTD111中碳化物的形貌多呈现汉字型,且更易分解。在900℃以上温度,GTD111的持久寿命远小于WZ-D2,这与2种合金中共晶相数量和尺寸、碳化物的分解、γ’相的演化密切相关。The microstructural evolution including γ’ phase, carbide and topologically close-packed(TCP) phase of GTD111 and designed alloy WZ-D2 were researched in directional solidification condition, heat treatment condition and ruptured at 980 ℃/190 MPa condition. The effects of these microstructural evolution on stress rupture property were also studied. The results show that the sizes and volume fractions of eutectic phase in WZ-D2 are both significantly less than those in GTD111. The γ’ phase area fraction of WZ-D2 is apparently more than that of GTD111 after heat treatment, and the γ’ phase cubic degree of WZ-D2 is slightly higher than that of GTD111. The morphology of MC carbides in GTD111 is mostly presented as Chinese characters and is more unstable. The stress rupture life of GTD111 are obviously shorter than that of WZ-D2 when the work temperature is above 900 ℃, which is closely related to the difference in quantity and size of eutectic phase, the morphology and decomposition of MC carbide, and the evolution of γ’ phase in the two alloys.

关 键 词：定向凝固合金 组织特征演变 持久寿命 

分 类 号：TG146.15[一般工业技术—材料科学与工程]