钛合金表面激光熔覆原位制备TiC/Ti_(2)Ni复合涂层微观组织及性能研究  

Microstructure and Properties of In-situ TiC/TiNi Composite Coating Prepared via Laser Cladding on Titanium Alloy

作　　者：刘亚楠 谷米 孙荣禄[1,2] 赵宇培 朱玉俊[4] 杨雪娇 Liu Yanan;Gu Mi;Sun Ronglu;Zhao Yupei;Zhu Yujun;Yang Xuejiao(School of Mechanical Engineering,Tiangong University,Tianjin 300387,China;Tianjin Area Major Laboratory of Advanced Mechatronics Equipment Technology,Tianjin 300387,China;Jiangsu Key Laboratory of Green Catalytic Materials and Technology,School of Petrochemical Engineering,Changzhou University,Changzhou,Jiangsu 213164,China;Department of Pharmacy and Biomedical Engineering,Clinic College,Anhui Medical University,Hefei,Anhui 230012,China)

机构地区：[1]天津工业大学机械工程学院,天津300387 [2]天津市现代机电装备技术重点实验室,天津300387 [3]常州大学石油化工学院江苏省绿色催化材料与技术重点实验室,江苏常州213164 [4]安徽医科大学临床医学院药学与生物工程系,安徽合肥230012

出　　处：《中国激光》2021年第14期109-119,共11页Chinese Journal of Lasers

基　　金：国家自然科学基金(51371125);安徽医科大学临床医学院校级科研基金(2020XJ021)。

摘　　要：为了有效改善Ti811合金表面硬度及耐磨性能,利用同轴送粉法在Ti811表面制备了激光熔覆复合涂层。采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、场发射电子探针显微镜(EPMA)、维氏硬度计及摩擦磨损试验机,系统地分析并研究了涂层的物相组成、微观组织、元素分布、显微硬度及摩擦磨损性能。结果表明:涂层生成相主要包括α-Ti固溶体、陶瓷增强相TiB_(2)和TiC及金属间化合物Ti_(2)Ni。涂层显微硬度的提高主要归功于弥散强化及固溶强化效应,最高可达902 HV,较基材显微硬度提高了2.37倍。涂层的磨损体积较基材下降了约27.9%,摩擦系数稳定在0.38~0.42,磨损机理主要为黏着磨损和轻微的磨粒磨损,具有优异的耐磨性能。Objective Titanium alloys have low density, high specific strength, and excellent corrosion resistance, thus they are commonly used in the engineering field to improve the mechanical properties of structural parts. However, their usage for various industrial applications is severely constrained owing to low hardness and poor wear properties. Several critical studies have been conducted regarding the surface modification of titanium alloys to solve their defects, including thermal spray, ion implantation, vapor deposition, and laser cladding, which have effectively improved their mechanical properties. In this work, a laser cladding composite coating was prepared on the Ti811 surface using the coaxial powder feeding method to improve the micro-hardness and wear resistance of the Ti811 alloy. The coating microstructure was characterized to study its phase compositions and elemental distribution. Moreover, the micro-hardness, friction, and wear properties of the coating were tested, and the CeO_(2) dispersive strengthening mechanism in the coating was revealed. The research results here can provide a valuable experimental and analysis basis for studying the laser cladding of composite coatings on Ti811 alloys.Methods The TruLaser Cell 7040 laser-processing center with a 4 kW laser at a 1030 nm wavelength was used for the laser cladding process.The coaxial powder feeding laser cladding technology was developed to synthesize the TiC/Ti_(2)Ni composite coating.The laser process parameters are as follows:laser power of 900 W,scanning speed of 400 mm/min,powder feeding speed of 5.0 g/min,protective gas flow of 11 L/min,powder feeding gas flow of 7 L/min,spot diameter of 3 mm,and working distance of 16 mm.The chemical compositions(mass fractions)of the materials used for laser cladding are Ni60(74%),TC4(20%),NiCr-Cr_(3)C_(2)(5%),and CeO_(2)(1%).A Ti811(Ti-8 Al-1 Mo-1 V)cuboid specimen of 40 mm× 30 mm × 8 mm was used as the substrate material.The chemical compositions(mass fractions)of the substrate are Al(8.1%),Mo(1.05%

关 键 词：激光技术 TI811合金 激光熔覆 微观组织 显微硬度 耐磨性能 

分 类 号：TG174.44[金属学及工艺—金属表面处理]