华南理工大学学报(自然科学版) ›› 2024, Vol. 52 ›› Issue (3): 10-17.doi: 10.12141/j.issn.1000-565X.230061

• 材料科学与技术 • 上一篇    下一篇

TC4表面激光熔覆硬质复合涂层组织与性能

付宇明 马顺芯 刘绍峰 郑立娟   

  1. 燕山大学 机械工程学院,河北 秦皇岛 066004
  • 收稿日期:2023-02-21 出版日期:2024-03-25 发布日期:2023-04-04
  • 作者简介:付宇明(1971-),男,博士,教授,主要从事激光熔覆及高熵合金新材料制备等研究。Email: mec9@ysu.edu.cn
  • 基金资助:
    河北省自然科学基金资助项目(E2021203218)

Microstructure and Properties of Laser Cladding Hard Composite Coating on TC4 Surface

FU Yuming MA Shunxin LIU Shaofeng ZHENG Lijuan   

  1. School of Mechanical Engineering,Yanshan University,Qinhuangdao 066004,Hebei,China
  • Received:2023-02-21 Online:2024-03-25 Published:2023-04-04
  • About author:付宇明(1971-),男,博士,教授,主要从事激光熔覆及高熵合金新材料制备等研究。Email: mec9@ysu.edu.cn
  • Supported by:
    the Nature Science Foundation of Hebei Province(E2021203218)

摘要:

TC4凭借比强度高、耐腐蚀性好、质量轻等一系列优点,被广泛应用于航空航天领域,但其摩擦系数大、耐磨性差等缺点极大地限制了其应用范围,针对TC4硬度低、耐磨性差等缺点,采用4 kW大功率Laser4000半导体激光器,选用过渡族难熔碳化物HfC、TaC和ZrC作为增强相,以H13钢基粉末作为基粉,利用激光熔覆技术在TC4表面制备了不同比例的钢基金属 — 陶瓷硬质涂层。之后利用扫描电镜(SEM)、EDS能谱仪、D/max-2500/PC型X射线衍射仪(XDR)等试验手段对不同比例涂层的宏观形貌、显微组织、物相组成和涂层元素分布等进行对比分析,利用Qness型号维氏显微硬度计测试涂层硬度并分析熔覆试样截面微观硬度变化规律,利用MMU-5G型端面摩擦磨损试验机研究了不同材料组分涂层的摩擦磨损性能,研究结果表明:试件熔覆层与基材形成了良好的冶金结合,熔覆层组织形态主要以枝晶组织以及块状组织为主,各熔覆层的主要物相中均含有TiC,随着三元陶瓷粉末含量的增加,MC的含量也随之增加,当碳化物混合粉末添加量为15%(质量分数)时,熔覆层中检测到Hf0.8Ta0.2Fe2三元合金相。当三元陶瓷粉添含量为10%(质量分数)时,熔覆层晶粒最为细小,涂层平均硬度最高,平均硬度约为763.43 HV,是基材硬度的2.29倍,当三元陶瓷粉末含量为5%(质量分数)时涂层的耐磨性最好,相对耐磨性为25%。

关键词: TC4钛合金, 激光熔覆, 金属陶瓷涂层, 过渡族碳化物

Abstract:

TC4 is widely used in aerospace field due to its high specific strength, good corrosion resistance and light weight. However, its disadvantages such as large friction coefficient and poor wear resistance greatly limit its application range. In view of the shortcomings of low hardness and poor wear resistance of TC4, a 4 kW high-power Laser4000 semiconductor laser was used to prepare different proportions of steel-based metal-ceramic hard coatings on the surface of TC4 by laser cladding technology with transition family refractory carbides HfC, TaC and ZrC as reinforcing phases and H13 steel-based powder as base powder. Then, the macro morphology, microstructure, phase composition and coating element distribution of the coatings with different proportions were compared and analyzed by means of scanning electron microscopy (SEM), EDS energy spectrometer, D/max-2500/PC X-ray diffractometer (XDR) and other test methods. The hardness of the coating was tested by Qness Vickers microhardness tester and the variation law of the microhardness of the cross section of the cladding sample was analyzed. The friction and wear properties of the coatings with different material components were studied by MMU-5G end friction and wear tester. The results show that the cladding layer of the specimen forms a good metallurgical bonding with the substrate. The microstructure of the cladding layer is mainly dendritic structure and block structure. The main phases of each cladding layer all contain TiC, and as the content of ternary ceramic powder increases, the content of MC also increases. When the carbide mixed powder is 15% (mass fraction), Hf0.8Ta0.2Fe2 ternary alloy phase is detected in the cladding layer. When the content of ternary ceramic powder is 10% (mass fraction), the cladding grain is the smallest, the average hardness of the coating layer is the highest, and the average hardness is about 763.43 HV, 2.29 times the hardness of the substrate. When the content of ternary ceramic powder is 5% (mass fraction), the coating has the best wear resistance, and the relative wear resistance is 25%.

Key words: TC4 titanium alloy, laser cladding, cermet coating, transition carbide

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