| 引用本文: | 徐宇轩,王兴,郭跃芬,周海滨,周佩禹,康丽,邓敏文,姚萍屏.表面改性WC颗粒增强铜基复合材料的微观结构与摩擦学特性[J].中国表面工程,2024,37(3):165~174 |
| XU Yuxuan,WANG Xing,GUO Yuefen,ZHOU Haibin,ZHOU Peiyu,KANG Li,DENG Minwen,YAO Pingping.Microstructure and Tribological Performance of Cu Matrix Composites Reinforced with Cu-modified WC Particles[J].China Surface Engineering,2024,37(3):165~174 |
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| 摘要: |
| WC 与 Cu 界面结合强度不足严重影响铜基复合材料的摩擦磨损性能，但业内尚未有良好的界面调控措施以优化性能。 采用铜表面改性 WC 颗粒改善 WC 与 Cu 基体界面，经粉末冶金工艺制备 Cu 改性 WC 颗粒增强铜基复合材料，开展复合材料的微结构表征与摩擦学性能研究。研究表明，Cu 改性 WC 颗粒可良好地嵌入铜基体，颗粒与 Cu 基体界面较基体弹性恢复能力提升 33%，硬度提升 20%。15 wt.% Cu 改性 WC 增强铜基复合材料具有最佳的物理性能与摩擦学特性，较纯铜粉末冶金材料体积密度提升 8%，布氏硬度提升 15%，摩擦因数波动幅度最小并稳定在 0.75，磨损量最小为 0.075 mm3 ，磨痕轮廓圆滑， 磨损面最完整且大面积成膜。随 Cu 改性 WC 含量增大，主要磨损机制由黏着磨损转变为剥离磨损，Cu 改性 WC 颗粒促进摩擦转移层的形成，抑制磨损面裂纹的横向扩展。Cu 改性 WC 颗粒与铜基体界面结合强度显著提升，15 wt.% 复合材料抑制黏着磨损与疲劳磨损，摩擦学性能优异。采用 Cu 改性 WC 颗粒增强铜基摩擦材料有望成为优化 WC 与 Cu 基体界面提升铜基复合材料摩擦学性能的重要备选途径。 |
| 关键词: Cu 改性 WC 铜基复合材料 界面 微观结构 摩擦学性能 |
| DOI：10.11933/j.issn.1007-9289.20230508001 |
| 分类号:TG156；TB114 |
| 基金项目:国家自然科学基金（52175209） |
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| Microstructure and Tribological Performance of Cu Matrix Composites Reinforced with Cu-modified WC Particles |
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XU Yuxuan1，WANG Xing1，GUO Yuefen1，ZHOU Haibin2，ZHOU Peiyu1，KANG Li1，DENG Minwen1，YAO Pingping1
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1.College of Powder Metallurgy, Central South University, Changsha 410083 , China ；2.Institute of Material Science and Engineering, Central South of Forestry and Technology,Changsha 410004 , China
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| Abstract: |
| Tungsten carbide (WC) particle-reinforced composites are widely used owing to their excellent mechanical properties. The limited solubility of WC in Cu and the weak mechanical interface between the WC particles and the Cu matrix are the main factors contributing to the suboptimal tribological performance of these composites. To address this issue, the surface modification of WC particles is crucial for optimizing the interface and enhancing the bonding strength between the particles and the matrix. In this study, porous spherical WC particles were modified with Cu via spraying and sintering. Cu matrix composites reinforced with five different amounts of Cu-modified WC particles (0 and 5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, and 25 wt.%) were prepared using a powder metallurgy technique. The mechanical and tribological properties of the Cu matrix composites were tested using a hardness tester and a UMT3 friction tester. Nanoindentation and scanning electron microscope (SEM) line scanning were used to characterize the interface of the Cu-mdified WC particles and Cu matrix. Macro-and microstructural characterization and tribological performance analysis were performed on Cu matrix composites reinforced with Cu-modified WC particles. The results of this study indicate that the Cu-modified WC particles were effectively embedded in the Cu matrix, resulting in the formation of a submicron diffusion layer at the interface between the modified particles and the matrix. This modification process led to a 33% increase in elastic resilience and a 20% increase in hardness at the interface. Microcracks within the particles as well as between the particles and Cu matrix contribute to an increase in porosity. Among the tested composites, the Cu-matrix composite reinforced with 15 wt.% Cu-modified WC particles exhibited superior tribological performance. The friction coefficients of this composite showed minimal fluctuations, stabilizing at approximately 0.75, with wear volumes decreasing to 0.075 mm3 . The worn surfaces of 15 wt.% Cu-modified WC reinforced composite displayed fairly smooth contours, the shallowest grinding crack, and large-scale continuous films. Furthermore, as the Cu-modified WC content increased, the main wear mechanism shifted from adhesive to abrasive wear at 15 wt.%, and eventually to fatigue wear at 25 wt.%. The surface friction transfer layers of the composites were characterized by the presence of Cu, Fe, O, and W. The Fe from the sliding friction pairs and absorbed oxygen contributed to the formation of a tribological film. Additionally, the presence of the modified particles causes deflection in the direction of the cracks and reduces their expansion at the corresponding locations. This research demonstrates a significant improvement in the interfacial bonding strength between the Cu-modified WC particles and Cu matrix. A composite material with 15 wt.% Cu-modified WC effectively inhibits adhesion wear and fatigue wear, resulting in excellent tribological properties. The utilization of Cu-modified WC particles to reinforce Cu-matrix composites offers a promising approach for optimizing the interface between WC and the Cu matrix, thereby enhancing the tribological properties of Cu-matrix composites. This paper has significant implications for the practical application of Cu-modified WC particles in Cu-matrix composites and provides a theoretical foundation for further research in this area. |
| Key words: Cu-modified WC particle Cu matrix composites interface microstructure tribology performance |
