摘要
难熔高熵合金在服役时的蠕变行为严重制约其工程化应用。本研究以(Ti_(39.5)Zr_(39.5)Nb_(9.7)Ta_(4.3)Mo_(7))_(100-x)Al_(x)(x=0、5、10、15、20,摩尔分数,%)难熔高熵合金为对象,分析了不同Al含量对合金微观组织和蠕变性能的影响。结果显示,Al含量较低时合金呈单一BCC相,而Al含量较高时析出B2和Al_(3)Zr相,且部分Al固溶于BCC基体使晶格收缩;Al添加可提高合金纳米硬度,添加20%Al的合金纳米硬度达6.85 GPa(在50 mN峰值载荷下);Al添加能降低合金蠕变总位移,且高Al含量下合金应变率敏感性指数更低,抗蠕变性能更优。本研究为难熔高熵合金成分优化及蠕变性能提升提供了理论依据。
The creep behavior of refractory high-entropy alloys(RHEAs)during service significantly limits their engineering applications.To address this issue,the effects of varying Al content on the microstructure and creep properties of(Ti_(39.5)Zr_(39.5)Nb_(9.7)Ta_(4.3)Mo_(7))_(100-x)Al_(x)(x=0,5,10,15,20,molar fraction,%)RHEAs were investigated.The results indicate that the alloy exhibits a single BCC phase at low Al content,while B2 and Al_(3)Zr phases precipitate at high Al content,with partial solid solution of Al into the BCC matrix causing lattice contraction.The Al addition enhances nanohardness of the alloy,and the nanohardness of the alloy with 20%Al addition reaches 6.85 GPa under a peak load of 50 mN.Furthermore,Al addition reduces the total creep displacement of the alloy.The alloy with higher Al content exhibits a lower strain rate sensitivity exponent and superior creep resistance.This study provides a theoretical basis for optimizing the composition and enhancing the creep properties of refractory high-entropy alloys.
作者
钟丽琼
韩娟
易艳良
ZHONG LI-qiong;HAN JUAN;YI YAN-liang(School of Mechanical Engineering,Guiyang University,Guiyang 550005,China;College of Chemistry and Materials,Jinan University,Guangzhou 510632,China;Shaoguan Research Institute of Jinan University,Shaoguan 512027,China)
出处
《稀有金属与硬质合金》
北大核心
2025年第6期120-126,共7页
Rare Metals and Cemented Carbides
基金
贵州省自然科学基金项目(黔科合基础-ZK[2024]一般522号)
贵阳学院博士研究启动基金项目(GYU-KY-[2025])
广东省基础与应用基础研究基金项目(2024A1515012353)
广州市科技计划项目(2024A04J4063)。
关键词
难熔高熵合金
Al添加
蠕变性能
应变率敏感性指数
纳米压痕
硬度
物相
refractory high-entropy alloy
Al addition
creep property
strain rate sensitivity exponent
nanoindentation
hardness
phase
