316L车板上激光增材WC/Fe材料组织结构及耐磨性能分析  

Synthesisand Characterization of WC-Reinforced Fe-Based Coatings by Laser Additive Manufacturing

作　　者：田振芳 张明[2] Tian Zhenfang;Zhang Ming(Department of Vehicle Engineering,Shanxi Vocational and Technical College of Communications,Taiyuan 030024,China;School of Mechanical Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]山西交通职业技术学院车辆工程系,太原030024 [2]太原理工大学机械工程学院,太原030024

出　　处：《真空科学与技术学报》2020年第11期1039-1043,共5页Chinese Journal of Vacuum Science and Technology

基　　金：山西省自然科学基金项目(编号:20140321014-02)。

摘　　要：选择激光增材方法处理WC与铁基粉制得WC增强铁基材料,测试了各层显微组织结构、物相与耐磨性能。研究结果表明:在结合区和热影响区之间形成了明显分界,增材和基体组织间形成紧密冶金结合状态,在增材中形成明显的胞状晶组织,在增材中形成了许多鱼骨性的树枝晶组织。在增材的截面区域形成了阶梯状的显微硬度分布特征,增材截面硬度达到1026 HV。在底部增材区中发生了硬度减小,热影响区内形成了许多针形的马氏体。中层区达到了0.31 mg/mm^2的较小磨损率,与基体相比发生了明显减小。析出了尺寸更大的碳化物硬质颗粒,获得更低的摩擦系数并提高了表面硬度,由此获得了比基体组织更强的耐磨性。The microstructures and tribological properties of the WC-reinforced Fe-based thick coatings,synthesized by laser additive manufacturing with WC and Fe-based powders on substrate of 316 L stainless steel,were characterized with X-ray diffraction,scanning electron microscopy,energy dispersive spectroscopy and mechanical probes.The results show that the WC-reinforced Fe-based coating significantly modified the microstructures and tribological properties.Generally speaking,the well-defined boundary formed between the interfacial bonding zone and heat affected zone(HAZ);the cellular grains,fish-bone-like dendric texture and martensite"needles"coexisted in HAZ.The top-down hardness profile decreased from 1026 HV,roughly in three deep-steps,and the depth wear-rate distribution changed in a decrease-increase mode,minimizing to 0.31 mg/mm^2 and being much lower than that of the substrate.The precipitation of large carbide grains possibly resulted in a stronger surface hardness and a lower friction coefficient.

关 键 词：激光增材制造 WC 第二相强化 显微组织 显微硬度 耐磨性 

分 类 号：TG174.44[金属学及工艺—金属表面处理]