不同纳米WS2含量Ni-P-Ti N-WS_(2)复合化学镀层的制备及其摩擦学性能EI北大核心CSCD

Ni-P-TiN化学复合镀层具有比Ni-P镀层更高的硬度和耐磨性,但其表面粗糙度大,与对偶件之间的摩擦因数高,应用潜力受到限制。通过在化学镀液中添加不同用量的纳米WS_(2)颗粒和固定用量的TiN颗粒,在低碳钢表面制备Ni-P-TiN-WS_(2)复合镀层。采用X射线能谱仪(EDS)、扫描电子显微镜(SEM)和X射线衍射仪(XRD)对镀层的化学成分(质量分数)、表面形貌及微观结构进行表征,并利用球盘式摩擦磨损试验机测试复合镀层的摩擦磨损性能。结果表明:纳米WS_(2)颗粒与纳米TiN颗粒的共沉积可使镀层表面更加致密、平整。随着镀液中纳米WS_(2)用量的增加,复合镀层的硬度先减小后增大,与氮化硅陶瓷球的摩擦因数则先升后降,磨损率显著下降,耐磨性增强。镀液中纳米WS_(2)粉末的用量为2.5 g/L时复合镀层的摩擦学性能最佳。纳米WS_(2)颗粒的加入及用量优化可显著改善复合镀层的综合性能,可为发展高耐磨低摩擦因数的先进涂层提供借鉴。

Preparation and Tribological Properties of Ni-P-TiN-WS2 Electroless Composite Coatings with Various Contents of Nano-WS2

Ni-P-TiN electroless coating has higher hardness and better wear resistance than Ni-P electroless coating, however, its large roughness and high friction factor with the counterparts restrict its application potential. Ni-P-TiN-WS₂ composite coatings are prepared on the surface of mild steel using electroless plating with a controlled dosage of nano-WS₂ and a fixed dosage of nano-TiN particles in bath. The morphology, microstructure and chemical composition of the coatings are characterized by scanning electron microscopy (SEM), X-ray diffractometry (XRD) and energy disperse spectroscopy (EDS). The tribologiacl properties of the composite coatings are investigated by wear testing with a ball-on-disc configuration. The results show that the co-deposition of nano-WS₂ and nano-TiN particles can form a compact and smooth surface. With the increase of nano-WS₂ dosage in bath, the Vickers hardness of the coatings decreases first and then increases, while the friction factor creases first and then decreases as sliding against Si₃N₄ balls, the wear rate of the composite coatings decreases significantly and the wear resistance have been enhanced. The composite coating deposited under a nano-WS₂ dosage of 2.5 g / L in bath exhibits the best tribological performance. The results that the addition of nano-WS₂ particles with the optimal dosage significantly improves the comprehensive performance of the composite coatings, can provide a reference for the development of advanced coatings with high wear resistance and low friction coefficient.