摘要
以粒径为53~106μm的TC4钛合金粗粉为原料,分别采用超音速火焰喷涂、大气等离子喷涂、激光熔覆及对超音速火焰喷涂涂层进行激光重熔等4种工艺在AA1060铝基体和Q235钢基体表面制备TC4钛合金涂层,对比研究了不同工艺下涂层的物相组成、微观结构、耐腐蚀性能与耐磨性能。结果表明:超音速火焰喷涂涂层和大气等离子喷涂涂层主要以α相为主,等离子喷涂涂层还含有一定量的TiO相,这2种涂层与基体的结合方式为机械结合,孔隙率较高;铝基体表面激光熔覆涂层和激光重熔超音速火焰喷涂涂层的主要物相为α相,而Q235钢基体表面则为β相,这2种涂层与基体的结合方式均为冶金结合,结构更加致密,晶粒更加细小,孔隙率极低。大气等离子喷涂涂层的平均硬度可达476 HV,约为超音速火焰喷涂涂层的2倍,激光熔覆涂层和激光重熔超音速火焰喷涂涂层的平均硬度分别超过550,600 HV;Q235钢基体表面涂层的硬度高于铝基体表面的涂层。大气等离子喷涂涂层的平均结合强度均约为30 MPa,比超音速火焰喷涂涂层高30%以上。在质量分数3.5%NaCl溶液中4种涂层按照自腐蚀电流密度从小到大的顺序依次为激光熔覆涂层、大气等离子喷涂涂层、激光重熔超音速火焰喷涂涂层、超音速火焰喷涂涂层。在铝基体表面,激光熔覆涂层的摩擦因数最小,大气等离子喷涂涂层的磨损率最小;在钢基体表面,激光重熔超音速火焰喷涂涂层的摩擦因数最小,激光重熔超音速火焰喷涂涂层和大气等离子喷涂涂层的磨损率相近,且小于其他2种涂层。大气等离子喷涂技术在采用粗粉制备TC4钛合金涂层方面具有最佳的性能与成本优势。
TC4 titanium alloy coating on the substrate surface of AA1060 Al and Q235 steel was prepared by four processes including high velocity oxygen-fuel spraying,atmospheric plasma spraying,laser cladding and laser remelting of high velocity oxy-fuel spraying coating by taking TC4 titanium alloy coarse power as raw materiats,respectively.The phase composition,microstructure,corrosion resistance and wear resistance of the coating under different processes were studied comparatively.The results show that the high velocity oxygen-fuel spraying coating and atmospheric plasma spraying coating were mainly compesed ofαphase,and the atmospheric plasma spraying coating also contained some TiO phase.The bonding mode between the two coatings and substrates was mechanical bonding,and the porosity was relatively high.The main phase of the laser cladding coating and laser remelting high velocity oxy-fuel spraying coating on the Al substrate surface was compesed ofαphase,while theβphase was on the Q235 steel substrate surface.The bonding mode of the two coatings with substrate was metallurgical bonding,the structure was relatively dense,the grains were relatively fine,and the porosity was extremely low.The average hardness of the atmospheric plasma spraying coating reached 476 HV,which was about twice that of the high velocity oxygen-fuel spraying coating.The average hardness of the laser cladding coating and laser remelting coating exceeded 550,650 HV,respectively.The hardness of coating on Q235 steel substrate surface was higher than that on Al substrate surface.The average bonding strength of atmospheric plasma spraying coating was about 30 MPa,which was more than 30%higher than that of high velocity oxy-fuel spraying coating.In the 3.5wt%NaCl solution,the four coatings in the order of free corrosion current density from small to large were laser cladding coating,atmospheric plasma spraying coating,laser remelting high velocity oxy-fuel spraying coating and high velocity oxy-fuel spraying coating.On the Al substrate surface,the friction coefficient of laser cladding coating was the smallest,and the wear rate of atmospheric plasma spraying coating was the smallest.On the steel substrate surface,the friction coefficient of laser remelting high velocity oxy-fuel spraying coating was the smallest,and the wear rate of laser remelting high velocity oxy-fuel spraying coating and atmospheric plasma spraying coating was similar,and smaller than those of the other two coatings.The atmospheric plasma spraying technology had the best performance and cost advantages in preparing TC4 coatings with coarse powders.
作者
汤军辉
段峻
纪秀林
TANG Junhui;DUAN Jun;JI Xiulin(Hangzhou Wiseking Surgical Robot Co.,Ltd.,Hangzhou 311100,China;Department of Mechanical Engineering,Shantou University,Shantou 515063,China;Sinopec Changling Branch,Yueyang 414012,China)
出处
《机械工程材料》
CAS
CSCD
北大核心
2024年第5期74-83,共10页
Materials For Mechanical Engineering
基金
国家自然科学基金资助项目(51875169)
汕头大学卓越人才计划项目(NTF21011)。
关键词
钛合金涂层
粗粉
激光熔覆
热喷涂
激光重熔
耐磨和耐腐蚀性能
titanium alloy coating
coarse powder
laser cladding
thermal spraying
laser remelting
corrosion and wear resistance
作者简介
汤军辉(1974-),男,江苏丹阳人,高级工程师,学士;通信作者:纪秀林教授。
