电刷镀Ni-CNTs/PTFE纳米复合镀层的摩擦磨损与耐腐蚀性能

再制造工程中很多表面镀层要求具有优异的摩擦磨损与耐腐蚀性能,利用纳米电刷镀技术在45钢基材上制备NiCNTs、Ni-CNTs/PTFE、Ni-WC/PTFE-CNTs复合镀层。采用XRD和SEM观察电刷镀复合镀层表面相结构和微观形貌,采用球盘式摩擦磨损试验机测试其在干摩擦条件下的摩擦磨损性能,采用动电位极化曲线研究其在3.5%NaCl溶液中的电化学腐蚀行为。结果表明:Ni-WC/PTFE-CNTs复合镀层耐磨性能最优,其次为Ni-CNTs/PTFE、Ni-CNTs复合镀层,均强于纯镍镀层;当CNTs质量浓度分别为1.5g/L和1.0g/L时,Ni-CNTs复合镀层分别表现出最优的摩擦磨损性能和最佳的耐腐蚀性能,Ni-WC/PTFE-CNTs、Ni-CNTs/PTFE复合镀层次之。纯镍镀层和Ni-CNTs复合镀层的磨损机制是粘着磨损,Ni-CNTs/PTFE复合镀层的磨损机制主要是粘着磨损,其次为磨粒磨损,Ni-WC/PTFE-CNTs复合镀层的磨损机制主要是磨粒磨损和接触疲劳磨损。

Friction-wear and Corrosion Resistance of Brush Plated Ni-CNTs/PTFE Nano-composite Coatings

The excellent wear resistance and corrosion resistance are needed for composite coating of remanufacturing parts. The composite coatings of Ni-CNTs, Ni-CNTs/PTFE and Ni-WC/PTFE-CNTs were prepared on 45 steel surfaces with brush pla-ting. The surface morphology and microstructure of coatings were observed by XRD or SEM, and the properties of dry friction and wear were measured by ball on disc wear tester, then the corrosion resistance was tested with potentiodynamic polarization curve in 3.5% NaCl solution. The results showed that the Ni-WC/PTFE-CNTs composite coating had the best wear resistance, and was followed by that of Ni-CNTs/PTFE and Ni-CNTs, which were all better than pure Ni coating. The wear resistance of the Ni-CNTs composite coating with 1.5 g/L was the best. The corrosion resistance of the Ni-CNTs composite coating with 1.0 g/L was the best, and was followed by the wear and corrosion resistance of Ni-WC/PTFE-CNTs, Ni-CNTs/PTFE composite coatings. The worn mechanism of pure Ni coating and Ni-CNTs composite coating were adhesive wear, while the worn mechanism of Ni-CNTs/PTFE composite coating was mainly adhesive wear, and was followed by abrasive wear, and the worn mechanism of Ni-WC/PTFE-CNTs composite coating was mainly abrasive wear and contact fatigue wear.