TiCu0.5Al0.5Cr0.2Ni0.1高熵合金微观组织及性能研究

Microstructure and Properties of TiCu0.5Al0.5Cr0.2Ni0.1 High-Entropy Alloy

采用X射线衍射仪、光学显微镜、扫描电镜和透射电镜对TiCu0.5Al0.5Cr0.2Ni0.1高熵合金的相组成、相形貌、元素分布进行了系统研究,利用显微维氏硬度计测量了合金在室温下的硬度,通过电子万能试验机对合金进行了室温压缩试验,并在实验室模拟环境下进行合金防腐防污性能研究。结果表明:TiCu0.5Al0.5Cr0.2Ni0.1高熵合金主要由六方晶系Ti(CuAl)2组成,大块状Ti(CuAl)2相间存在条状组织,条状为AlCu2Ti相,条间为CuTi2相。树枝晶(DR)内Al元素和Cr元素含量较高,枝晶间(ID)Ti元素含量高于枝晶区域,而Ni元素和Cu元素整体分布较均匀。枝晶间(ID)显微硬度平均值为772HV,树枝晶DR显微硬度为690HV,枝晶间(ID)显微硬度高于树枝晶(DR)的;室温压缩强度为1091MPa。合金耐腐蚀性能良好,60℃人造海水中合金腐蚀失重量仅为-0.00005 g,并具备一定的防污功能。

The phase composition,phase morphology and element distribution of TiCu0.5Al0.5Cr0.2Ni0.1 high-entropy alloy are researched by X ray diffraction,optical microscope,scanning electron microscopy(SEM)and transmission electron microscopy(TEM).Its hardness is measured with a vickers microhardness unit at room temperature.The compression tests atroom temperature are conducted by an electron universal testing machine.The anti-corrosion and anti-fouling properties of thealloys are studied in a laboratory simulation environment.Results show that the TiCu0.5Al0.5Cr0.2Ni0.1 high-entropy alloy is mainly composed of hexagonal crystal system Ti(CuAl)2phase.There is a strip structure between the bulk Ti(CuAl)2 phase,the strip is AlCu2Ti phase,and between the strips is CuTi2 phase.The content of Al and Cr in dendrite(DR)is higher than those in interdendritic region,the content of Ti in interdendritic(ID)is higher than that in dendrite region,and the distributionof Ni and Cu elements is more uniform.The average microhardness of interdendritic(ID)is 772 HV,higher than that of 690HV of dendritic(DR),and the compressive strength at room temperature is 1091 MPa.The alloy has excellent corrosion resistance and certain anti-fouling function,and the uniform corrosion weight loss in artificial seawater at 60℃is only-0.00005 g.