固溶冷却速率对镍基粉末高温合金组织性能的影响  

Effect of Solid Solution Cooling Rate on Microstructure and Properties of Nickel-Based Powder Superalloys

作　　者：柳翔宇 李超[1] 谢仲豪 LIU Xiang-yu;LI Chao;XIE Zhong-hao(State Key Laboratory for Powder Metallurgy,Central South University,Changsha 410083,China)

机构地区：[1]中南大学粉末冶金国家重点实验室,湖南长沙410083

出　　处：《稀有金属与硬质合金》2025年第1期125-132,共8页Rare Metals and Cemented Carbides

摘　　要：以涡轮盘用镍基粉末高温合金为研究对象,采用梯度冷却方法在单个试样上实现了γ′组织形貌及尺寸的梯度变化。通过扫描电镜观察和维氏硬度测试,探究了固溶冷却速率对合金组织和力学性能的影响;通过三维原子探针分析,探究了固溶冷却速率对γ相和γ′相元素偏析行为的影响。结果表明,随着固溶冷却速率的减小,γ′相尺寸逐渐增大后趋于稳定。在较快固溶冷却速率下γ′相尺寸较小,形状为近球形;在较慢固溶冷却速率下,γ′相呈现二次γ′相和三次γ′相分布,且二次γ′相尺寸较大。不同固溶冷却速率对γ相和γ′相元素分配无明显影响,Ni、Al、Ti、Nb四种元素主要分布在γ′相中,而Co、Cr、Mo三种元素主要分布在γ基体相中,W元素未观察到明显的偏析。由于采用梯度冷却实验方法,冷却速率范围过大,实验结果捕捉到多个硬度变化的拐点,合金硬度随着固溶冷却速率的降低呈现出非线性变化趋势。Taking nickel-based powder superalloys for turbine disks as the research object,gradient change of γ′microstructure morphology and size was achieved on a single sample by gradient cooling.The effect of solid solution cooling rate on the microstructure and mechanical properties of the alloy was investigated by scanning electron microscope observation and Vickers hardness test.The effect of solid solution cooling rate on the element segregation behavior in γ phase and γ′phase was investigated by three-dimensional atomic probe analysis.The results show that with the decrease of solid solution cooling rate,the size of γ′phase gradually increases and then tends to be stable.The size ofγ′phase is smaller and the shape is nearly spherical at a faster solid solution cooling rate.At a slower solid solution cooling rate,the γ′phase is distributed in the form of secondary γ′phase and tertiary γ′phase,and the size of the secondary γ′phase is larger.Different solid solution cooling rates have no obvious effect on the element distribution in γ phase and γ′phase.Ni,Al,Ti and Nb are mainly distributed in the γ′phase,while Co,Cr and Mo are mainly distributed in the γ matrix phase,and no obvious segregation of W element is observed.Due to the use of the gradient cooling experimental method,the range of cooling rate is too large,and multiple inflection points of hardness change are captured in the experimental results.The alloy hardness shows a nonlinear change trend with the decrease of solid solution cooling rate.

关 键 词：镍基粉末高温合金 固溶 冷却速率 γ'相 硬度 

分 类 号：TG132.32[一般工业技术—材料科学与工程]