Si含量对激光熔覆FeCrNiCSi_(x)涂层组织结构及高温摩擦性能的影响  

Effect of Si Content on Microstructure and High Temperature Friction Properties of FeCrNiCSi_(x)Coating by Laser Cladding

作　　者：龙海洋 史海江 卢冰文 马汝成 闫星辰 刘志存 贵永亮 董真 LONG Haiyang;SHI Haijiang;LU Bingwen;MA Rucheng;YAN Xingchen;LIU Zhicun;GUI Yongliang;DONG Zhen(North China University of Science and Technology,Hebei Tangshan 063210,China;Guangdong Provincial Key Laboratory of Modern Surface Engineering Technology,Institute of New Materials,Guangdong Academy of Sciences,Guangzhou 510651,China)

机构地区：[1]华北理工大学,河北唐山063210 [2]广东省科学院新材料研究所广东省现代表面工程技术重点实验室,广州510651

出　　处：《表面技术》2024年第17期62-70,共9页Surface Technology

基　　金：国家自然科学基金(52005113,52101082,52201067);广东省科学院打造综合产业技术创新中心行动资金(2022GDASZH-2022010107);广州市青年科技人才托举项目(QT-2023-038);广东省基础与应用基础研究基金(2022B1515250004);河北省属高校基本科研业务费研究项目(JQN2023029);河北省在读研究生创新能力培养资助项目(CXZZBS2024136);河北省省级科技计划(246Z1019G)。

摘　　要：目的研究不同Si含量对Fe基涂层组织结构及高温摩擦磨损性能的影响规律,为延长高温环境下冶金部件的服役寿命提供技术支持。方法选用铬粉、硅粉、镍粉、碳粉、铁粉(纯度均大于等于99%),配制不同Si含量(质量分数分别为5%、10%、15%)的FeCrNiCSi_(x)粉末,在配制完成后使用行星球磨机混合粉末,采用激光熔覆技术制备不同Si含量(质量分数分别为5%、10%、15%)的FeCrNiCSi_(x)涂层。通过X射线衍射仪(XRD)、扫描电子显微镜(SEM)和其自带能谱仪(EDS)分析涂层的物相组成、显微组织和元素分布;利用维氏显微硬度计分析涂层的截面显微硬度分布规律;采用摩擦磨损试验机测试涂层在温度500℃、载荷200 N下的摩擦因数,称量磨损实验前后的质量差,计算磨损率;通过SEM观察磨痕形貌,分析涂层磨损机理。结果质量分数为5%的Si涂层物相主要是γ-Fe和Fe-Cr固溶体,显微组织由树枝晶和等轴晶组成。质量分数为10%、15%的Si涂层的物相主要为Fe_(3)Si、Fe-Cr固溶体,显微组织主要由等轴晶组成。质量分数为5%、10%、15%的Si涂层的显微硬度分别为301.3HV0.5、576.6HV0.5、598.5HV0.5,摩擦因数分别为0.61、0.50、0.47,磨损率分别为3.10×10^(-5)、5.90×10^(-5)、7.39×10^(-5)g/m。结论随着涂层中Si含量的升高,涂层的摩擦因数降低,显微硬度和磨损率升高。其中,Fe_(3)Si相的产生使得涂层的平均显微硬度提高,由于Fe_(3)Si相的脆性较大,剥落程度较严重,导致涂层的磨损率上升。综合评判可知,质量分数为10%的Si涂层的高温耐磨最优,其磨损形式为磨粒磨损。After the key parts of metallurgical equipment are used in high temperature environment for a long time,the surface is easy to be damaged.In high temperature environment,the Fe-Cr-Si alloy coating can protect the substrate from high temperature gases,oxides and corrosive media,while providing high hardness and wear resistance.Therefore,it is widely used for surface protection of service parts in high temperature,high corrosion and high wear environments.At present,the main research pays more attention to Fe-Cr-Si coatings with low Si content,and less to Fe-Cr-Si coatings with high Si content.The coating prepared by laser cladding technology has the advantages of metallurgical bonding,low dilution rate,small heat-affected zone and dense microstructure.The preparation of protective coating by laser cladding technology is a suitable way to improve the service life of parts.The work aims to solve the problem of surface failure of metallurgical parts in high temperature environment and investigate the effect of Si content on the high temperature wear performance of Fe-based coatings.Therefore,chromium powder,silicon powder,nickel powder,carbon powder and iron powder(purity≥99%)were used to prepare alloy powder.The Si content of the alloy powder was 5%,10%and 15%.The finished powder was mixed with a star ball mill.After mixing,the powder was dried in a vacuum drying oven at 100℃for 2 h.The process parameters of laser cladding were as follows:laser power of 1600 W,lap rate of 50%,spot diameter of 5 mm,scanning speed of 600 mm/min and powder feeding speed of 5 r/min.The base material was 1Cr11Ni2W2MoV heat-resistant steel plate.The phase composition of the coating was analyzed by X-ray diffractometer.The microstructure of the coating and its element distribution were analyzed by scanning electron microscope(SEM)and its own energy dispersive spectrometer(EDS).The friction and wear properties of coatings with different Si contents were tested by friction and wear testing machine at 500℃,and the friction coefficient c

关 键 词：激光熔覆 Fe-Cr-Si合金 显微组织 显微硬度 高温磨损 磨损机理 

分 类 号：TG174.4[金属学及工艺—金属表面处理] TG665[金属学及工艺—金属学]