摘要
通过RFL-C1000锐科光纤激光器,选择不同的激光扫描速度在TC4合金表面制备TC4+Ni60/h-BN钛基复合涂层,利用SEM、XRD仪、EDS仪、显微硬度计、JA 2003数显电子精密天平、摩擦磨损试验机对复合涂层的组织、物相、硬度、磨损量、摩擦系数进行分析和测试,研究激光扫描速度对钛基复合涂层组织及性能的影响。实验结果表明,随着扫描速度的增加,熔覆层宽度、深度、稀释率逐渐减小,熔高呈现先增大后减小的趋势。不同激光扫描速度的熔覆层均由Ti 2Ni、TiN 0.3、TiC、TiB、α-Ti等物相组成。激光扫描速度较低时,增强相团聚区以网状形式分布在基底中,随着激光扫描速度的增加,熔覆层中各增强相形成块状相团聚区,以相互孤立的形式分布于基底中。提高激光扫描速度能够降低熔覆层磨损量和摩擦系数,并提高熔覆层硬度和耐磨性,但是过高的激光扫描速度会导致熔覆层出现气孔、裂纹等缺陷,还会影响熔覆层与基体的结合性能,因此综合考虑最佳激光扫描速度为10 mm/s。
The TC4+Ni60/h-BN Ti-based composite coatings were prepared on the surface of TC4 alloy by RFL-C1000 Raycus fiber laser with different laser scanning speeds.The microstructure,phase,hardness,wear mass loss and friction coefficient of the cladding coating were analyzed and tested by SEM,XRD,EDS,microhardness tester,JA 2003 digital display precision balance and friction wear tester.We studied the effect of laser scanning speed on the microstructure and properties of laser cladding coating.The experimental results showed that with the increase of scanning speed,the width,depth,and dilution rate of the laser cladding coating was decreased gradually,but the melting height first increased and then decreased.The cladding coatings with different laser scanning speed are composed of Ti 2Ni,TiN 0.3,TiC,TiB andα-Ti.When the laser scanning speed is low,the enhanced phase agglomeration area is distributed in the substrate by the form of a network.With the increase of scanning speed,the reinforcing phases in the cladding coating form a massive phase agglomeration zone,which is distributed in the substrate by an isolated form.Increasing the laser scanning speed can reduce the wear mass loss and friction coefficient of the cladding coating,improve the hardness and wear resistance of the cladding coating.However,excessive laser scanning speed can cause defects in the cladding coating,such as pores and cracks,which affects the bonding properties between the cladding coating and the substrate.So the optimal laser scanning speed is 10 mm/s.
作者
谭金花
孙荣禄
牛伟
刘亚楠
郝文俊
TAN Jinhua;SUN Ronglu;NIU Wei;LIU Yanan;HAO Wenjun(School of Mechanical Engineering,Tianjin Polytechnic University,Tianjin 300387,China;Tianjin Key Laboratory of Advanced Mechatronics Equipment Technology,Tianjin 300387,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2020年第12期12094-12100,共7页
Materials Reports
基金
国家自然科学基金(51371125)。
关键词
激光扫描速度
激光熔覆
钛合金
显微组织
硬度
耐磨性
laser scanning speed
laser cladding
titanium alloy
microstructure
hardness
wear resistance
