激光熔覆碳纳米管增韧铁基非晶涂层的组织与力学性能  

Microstructure and Mechanical Properties of Laser Cladding Carbon Nanotubes Toughened Fe-based Amorphous Coating

作　　者：王天聪 朱彦彦[1] 姚成武[1] 李铸国[1] WANG Tiancong;ZHU Yanyan;YAO Chengwu;LI Zhuguo(Shanghai Key Laboratory of Materials Laser Processing and Modification,School of Materials Science and Engineering,Shanghai Jiaotong University,Shanghai 200240,China)

机构地区：[1]上海交通大学材料科学与工程学院,上海市激光制造与材料表面改性重点实验室,上海200240

出　　处：《机械工程材料》2020年第5期54-59,65,共7页Materials For Mechanical Engineering

基　　金：国家自然科学基金青年科学基金资助项目(51805321);上海市青年科技英才扬帆计划项目(17YF1408700)。

摘　　要：采用球磨工艺将镀镍碳纳米管与铁基非晶粉体混合后,以同轴送粉激光熔覆方法在钢板上制备涂层,确定了最佳的球磨时间,并探讨镀镍碳纳米管质量分数(0~1.00%)对涂层组织与力学性能的影响。结果表明:铁基非晶粉体与镀镍碳纳米管的球磨混合时间控制在30min较为适宜;涂层均包括非晶区、等轴树枝晶区和柱状树枝晶区,随着镀镍碳纳米管质量分数的增加,涂层中非晶相面积分数降低,析出的纳米晶尺寸增大;镀镍碳纳米管的含量几乎不影响涂层中柱状树枝晶区和等轴树枝晶区的硬度;随着镀镍碳纳米管质量分数的增加,涂层中非晶区的平均硬度由1 615.0HV降低到1 464.3HV,断裂韧度由5.75 MPa·m^1/2提高至7.67 MPa·m^1/2。After the nickel-plated carbon nanotubes and iron-based amorphous powder were mixed by ball milling process,the coating was prepared on the steel plate by coaxial powder laser cladding method.The optimal ball milling time was determined,and the effect of the mass fraction of nickel-plated carbon nanotubes(0-1.00%)on the micro structure and mechanical properties of the coating was discussed.The results show that the proper ball milling time for mixing iron-based amorphous powder and nickel-plated carbon nanotubes was not longer than30 min.The coatings all consisted of amorphous region,equiaxed dendritic region and columnar dendritic region;with increasing mass fraction of nickel-plated carbon nanotubes,the area fraction of amorphous phase in the coating decreased,and the size of the precipitated nanocrystals increased.The content of nickel-plated carbon nanotubes hardly affected the hardness of the columnar dendrite and equiaxed dendrite regions in the coating.With increasing mass fraction of nickel-plated carbon nanotubes,the average hardness of the amorphous region in the coating decreased from1 615.0 HV to 1 464.3 HV,and the fracture toughness increased from 5.75 MPa·m^1/2 to 7.67 MPa·m^1/2.

关 键 词：激光熔覆 铁基非晶涂层 碳纳米管 组织 硬度 断裂韧性 

分 类 号：TG17[金属学及工艺—金属表面处理]