摘要
目的研究不同层数高熵合金涂层的耐磨性和耐腐蚀性。方法采用激光熔覆技术在Q345钢表面制备FeCoNiCr_(0.5)Al_(0.2)高熵合金涂层。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、摩擦磨损试验机等研究高熵合金涂层的组织结构,并表征其性能。结果高熵合金涂层与基体Q345钢实现了良好的冶金结合。当涂层大于3层时,稀释率达到理想区间,涂层表面主要由细小的等轴晶和柱状组织组成。随着涂层层数的增加,相结构逐渐转变为FCC相,涂层表面Fe的原子数分数从66.72%降至30.46%,稀释率由37.7%降至9.8%。1层涂层的硬度最高,达到422HV0.5,约为基体的3.5倍;当涂层层数大于3时,表面的平均硬度为190HV0.5左右,是基体的1.5倍左右。在空气中,涂层相较于基体,在10、20 N载荷下磨损率分别下降了23.3%~37.1%、8.4%~21.0%。在质量分数3.5%的NaCl溶液中,涂层相较于基体,在10、20 N载荷下磨损率分别下降了38.4%~45.5%、43.9%~47.7%。在10、20 N载荷下,涂层在空气中的磨损率分别是在质量分数3.5%的NaCl溶液中的6倍、4.5倍左右。与基体相比,1、3、5层涂层的腐蚀电位分别提升了11.9%、57.6%、50.2%,腐蚀电流密度下降了1~2个数量级。结论随着高熵合金涂层层数的增加,稀释率降低,硬度提高,耐磨性和耐腐蚀性大幅提升,根据不同的性能需求可以灵活选择制备不同层数的涂层。
The harsh service environment of offshore wind power equipment makes the wear and corrosion of its components very serious,especially the corrosion of offshore wind turbine tower.FeCoNiCr_(0.5)Al_(0.2) high entropy alloy coatings were prepared on the surface of Q345 steel,a commonly used material for tower tubes,by laser cladding technology,and their tribological properties were investigated in air and 3.5%NaCl simulated seawater solution.The effects of the number of coating layers on microstructure,hardness,dilution rate,wear rate and polarization curves were investigated by studying the microstructure,dilution rate,hardness,dilution rate,abrasion and corrosion resistance of the high entropy alloy coatings with different numbers of layers.The high entropy alloy coating realized excellent metallurgical bonding with the base Q345 steel.The number of coating layers increased from 1 to 5,the Fe element content on the surface of the coating gradually decreased from 66.72%to 30.46%,and the dilution rate decreased from 37.7%to 9.8%,the surface of the coating mainly consisted of fine isometric crystals and columnar organization,and the phase structure gradually changed to simple FCC phase with the increase of the number of coating layers.The hardness of the 1-layer coating was the highest,which was 422HV0.5,about 3.5 times that of the substrate.When the number of coating layers was greater than 3,the average hardness of the coating was 190HV0.5,which was about 1.5 times of that of the substrate.The wear rate of the coating in both air and 3.5%NaCl solution was lower than that of the Q345 steel substrate.In air,the coatings with 1,3 and 5 layers,compared to the substrate,showed a 37.1%,23.3%,and 26.3%decrease in wear rate at 10 N load,and 21.0%,8.4%,and 11.7%decrease in wear rate at 20 N load,respectively.In 3.5%NaCl solution,the wear rate of coatings with 1,3 and 5 layers,compared to the substrate,decreased by 45.5%,38.4%and 40.2%respectively at 10 N load,and 47.7%,43.9%and 42.4%respectively at 20 N.The wear rate of the
作者
张国建
程西云
纪秀林
卢羿汛
陈俊炜
李赐临
胡阳东
ZHANG Guojian;CHENG Xiyun;JI Xiulin;LU Yixun;CHEN Junwei;LI Cilin;HU Yangdong(College of Engineering,Shantou University,Guangdong Shantou 515063,China)
出处
《表面技术》
EI
CAS
CSCD
北大核心
2024年第21期187-197,共11页
Surface Technology
基金
广东省自然科学基金(2014A030313479)。
关键词
激光熔覆
高熵合金涂层
层数
稀释率
耐磨性
耐腐蚀性
laser cladding
high entropy alloy coating
number of layers
dilution rate
wear resistance
corrosion resistance
