摘要
制备了不同Cr含量的Cr_(x)MoNbTiV(x=0.2、0.4、0.6、0.8和1.0,摩尔比)难熔高熵合金,并在800℃下进行高温抗氧化试验,研究了Cr元素对合金铸态组织、氧化膜宏微观组织的影响。结果表明,Cr_(x)MoNbTiV合金在铸态时均为单一的体心立方结构,呈典型的枝晶状组织,Ti、Cr在枝晶间富集,Mo和Nb在枝晶富集,V无明显偏析。在800℃氧化不同时间后,Cr_(x)MoNbTiV合金表面形成不同的氧化物,氧化膜出现不同程度的偏析。随着Cr含量增加,氧化膜的厚度明显变薄,高度差变小,外层疏松氧化物越来越少,表面平整度增加。当Cr含量由x=0.2增加到x=1.0时,合金表面的氧化膜厚度由340μm减小至65μm,氧化膜的表面高度差由55.96μm减小至20.16μm,合金的抗氧化性能大幅提升。
CrxMoNbTiV(x=0.2,0.4,0.6,0.8 and 1.0)refractory high entropy alloys with different Cr contents were prepared,and high temperature oxidation tests at 800℃were conducted.The as-cast microstructure,macro and micro structure of oxidation film were investigated.The results indicate that as-cast CrxMoNbTiV alloys with different Cr contents exhibit single body-centered cubic(BCC)structure and present typical dendrite structure.Ti and Cr are enriched in interdendritic area,while Mo and Nb are enriched in the dendritic area,and segregation for element V is hardly observed.After oxidation at 800℃for different durations,different oxidation products are generated on the surface of CrxMoNbTiV alloys,and segregation occurs on oxide film to different degrees.The thickness and height difference of oxidation film are decreased with increasing in Cr,and outer loose oxide is reduced,leading to a higher flatness.With Cr content rising from 0.2 to 1.0,the thickness of surficial oxidation film is decreased from 340μm to 65μm,and the height difference is decreased from 55.96μm to 20.16μm,significantly improving the oxidation properties.
作者
徐琴
王琪
赵甲丁
殷亚军
陈瑞润
XU Qin;WANG Qi;ZHAO Jiading;YIN Yajun;CHEN Ruirun(School of Mechanic and Electrical Engineering,Henan University of Technology,Zhengzhou 450001;National Key Laboratory for Precision Hot Processing of Metals,Harbin Institute of Technology,Harbin 150001;State Key Laboratory of Materials Processing and Die&Mould Technology,School of Materials Sci-ence and Engineering,Huazhong University of Science and Technology,Wuhan 430074)
出处
《特种铸造及有色合金》
北大核心
2025年第11期1630-1636,共7页
Special Casting & Nonferrous Alloys
基金
国家自然科学基金资助项目(52001114,51825401)
河南省高校科技创新人才支持计划资助项目(23HASTIT022)
华中科技大学材料成形与模具技术全国重点实验室开放基金资助项目(P2023-005)
河南省高等学校青年骨干教师培育计划资助项目(2021GGJS064)。
关键词
难熔高熵合金
氧化膜
组织特征
抗氧化性能
Refractory High Entropy Alloy
Oxidation Film
Microstructure Characteristics
Oxidation Resistance
