摘要
This work investigated tribological behavior and corrosion resistance of laser cladding(LC)Ti_(50)Nb_(15)V_(15)Zr_(5)Cr_(5)Al_(10)high-entropy alloy(HEA)coatings on Ti6Al4V substrates.Microstructural characterization illustrated that there was only body centered cubic phase in the HEA coating.Besides,the coatings of different laser power all exhibited obviously higher hardness than the substrate.It is illustrated that the microstructure of the HEA coatings is composed of body centered cubic phase,and the temperature gradient contributes to the distribution difference between the equiaxed and columnar grains.Meanwhile,the relationships between the tribological behavior,corrosion resistance and alloying elements have been illustrated.The HEA coating with 2200 W holds the best wear and corrosion resistance.During the friction process,there are many oxides formed at high temperatures,and adhesive wear contributes most to the wear mechanism of the coatings.The wear volumes of the HEA coatings are only 24.7%to 45.5%of that of the Ti6Al4V substrate.Due to the alloying elements like Cr and Al,there is dense passive film formed during the corrosion process,thereby leading to better corrosion resistance of the coatings.The corrosion rates of the HEA coatings with 2200 W and Ti6Al4V substrate are 5.34×10^(-3)mm/a and 2.69×10^(-2)mm/a,respectively.
本研究对激光熔覆Ti_(50)Nb_(15)V_(15)Zr_(5)Cr_(5)Al_(10)高熵合金(HEA)涂层在Ti6Al4V基体上的摩擦学行为和耐腐蚀性进行了研究。微观结构表征表明,HEA涂层中仅存在体心立方相。此外,不同激光功率的涂层硬度均明显高于基体。结果表明,HEA涂层的微观结构由体心立方相组成,温度梯度造成了等轴晶和柱状晶的分布差异。同时,本研究还阐明了摩擦学行为、耐腐蚀性与合金元素之间的关系。激光功率为2200 W的HEA涂层具有最佳的耐磨性和耐腐蚀性。在摩擦过程中产生的高温下会形成大量氧化物,黏着磨损是涂层磨损机制的主要因素。HEA涂层的磨损体积仅为Ti6Al4V基底的24.7%至45.5%。由于Cr和Al等合金元素的存在,HEA涂层在腐蚀过程中会形成致密的钝化膜,从而使得涂层具有更好的耐腐蚀性。2200 W和Ti6Al4V基底的高熵合金涂层的腐蚀速率分别为5.34×10^(-3)mm/a和2.69×10^(-2)mm/a。
基金
Projects(2022YFC2406000,52201067)supported by the National Natural Science Foundation of China
Project(2019BT02C629)supported by the Guangdong Special Support Program,China
Project(2022GDASZH-2022010107)supported by the Guangdong Academy of Science Projects,China
Project(2022GDASZH-2022010203-003)supported by GDAS Projects of International Cooperation Platform of Science and Technology,China
Project(2022B1515250004)supported by the Guangdong Basic and Applied Basic Research Foundation,China
Projects(2023B1212120008,2023B1212060045)supported by the Guangdong Province Science and Technology Plan Projects,China
Project(2024KTSCX191)supported by the Guangdong Province General University Characteristic Innovation Project,China
Project(SKXRC202403)supported by the Guangdong Association for Science and Technology,China
Projects(QT-2023-038,QT2024-016)supported by the Young Talent Support Project of Guangzhou Association for Science and Technology,China
Project(023AFB057)supported by the Natural Science Foundation of Hubei Province,China
Project(2023780200040009603)supported by the Jiangmen Science and Technology Plan Projects,China。
