激光扫描速度对IN718涂层组织与摩擦磨损性能的影响  

Effects of Laser Scanning Speed on Microstructure and Wear Resistance of Inconel 718 Coatings

作　　者：王涛[1] 王宁[1] 朱磊 雷剑波[2] WANG Tao;WANG Ning;ZHU Lei;LEI Jianbo(Aerospace Engineering College,Civil Aviation University of China,Tianjin 300300,China;Laser Engineering Research Institute,Tianjin Polytechnic University,Tianjin 300387,China)

机构地区：[1]中国民航大学航空工程学院,天津300300 [2]天津工业大学激光技术研究所,天津300387

出　　处：《热加工工艺》2022年第10期79-84,共6页Hot Working Technology

基　　金：国家自然科学基金民航联合基金项目(U1633104);中央高校科研基本业务费项目(3122017017);天津市教委科研计划项目(2019KJ119);中国民航大学研究生科技创新项目(10502729)。

摘　　要：采用同轴送粉式激光熔覆技术成功制备了扫描速度分别为6、10、14、18 mm/s的IN718涂层。研究了4种扫描速度下IN718涂层的宏观形貌、微观组织和成分分析,并分析了4种扫描速度对IN718涂层的显微硬度和摩擦磨损性能的影响。结果表明,当扫描速度为14 mm/s时涂层的宏观成形质量最优,熔覆层薄厚均匀。随激光扫描速度的增加,激光线扫描能量密度下降,熔池几何尺寸减小。每种扫描速度下的熔覆层微观结构主要由胞状晶、柱状枝晶和等轴晶组成。当扫描速度为14 mm/s时,熔覆层的晶粒更加致密,尺寸更加细小,熔覆层与基体结合紧密,无熔渣、微孔裂纹等缺陷。随扫描速度的增加,熔覆层的磨损率先减少后增加,当扫描速度为14 mm/s时,熔覆层的磨损率最低为0.02114 mg/m。IN718 coatings with the scanning speeds of 6 mm/s, 10 mm/s, 14 mm/s and 18 mm/s were successfully fabricated by coaxial powder feeding laser cladding. The macro morphology, microstructure and composition of IN718coating at four scanning speeds were studied, and the effects of four scanning speeds on the microhardness and friction and wear properties of IN718 coating were analyzed. The results show that when the scanning speed is 14 mm/s, the macro forming quality of the coating is best, and the thickness of the cladding layer is uniform. With the increase of laser scanning speed, the energy density of laser line scanning decreases and the geometry size of molten pool decreases. The microstructure of the cladding layer at each scanning speed is mainly composed of cellular crystal, columnar dendrite and equiaxed crystal.When the scanning speed is 14 mm/s, the cladding layer has more compact grains and smaller size, and the cladding layer is closely bonded with the substrate, without slag, micro cracks and other defects. With the increase of scanning speed, the wear rate of the cladding layer first decreases and then increases. When the scanning speed is 14 mm/s, the lowest wear rate of the cladding layer is 0.02114 mg/m.

关 键 词：激光熔覆 扫描速度 IN718熔覆层 微观组织 摩擦磨损 

分 类 号：TG174.4[金属学及工艺—金属表面处理]