混杂比对AZ91D纳米复合材料油润滑摩擦磨损行为的影响

摘要

使用MRS-10P型四球摩擦试验机对AZ91D镁合金及不同混杂比碳纳米管和纳米碳化硅增强AZ91D镁合金复合材料在油润滑条件下的摩擦磨损行为进行研究.在加载载荷为200~1000 N、主轴转速为380 r/min时测试 AZ91D 及其复合材料的摩擦因数和磨损率,采用扫描电子显微镜(SEM)、X 射线衍射仪(XRD)和能谱分析仪(EDS)分析磨损表面形貌、相和元素组成,并讨论碳纳米管和纳米碳化硅的协同作用机制.结果表明,与AZ91D镁合金相比,由少量碳纳米管和纳米碳化硅混杂增强的 AZ91D 镁基纳米复合材料具有更好的耐磨性能和不同的磨损机理, 质量分数分别为0.5%的碳纳米管和纳米碳化硅增强的AZ91D镁合金基纳米复合材料具有最好的摩擦性能.镁基混杂纳米复合材料的磨损机理为微犁沟、微切削、轻微磨粒及脱粘磨损的复合形式.%Friction and wear behavior of AZ91D and its nanocomposites reinforced by different contents of hybrid multi-walled CNTs and nano-SiC particulates under oil lubrication was investigated using a MRS-10P four-ball tribometer. Friction coefficients and wear rates were measured within a load range of 200–1000 N at a spindle rotary speed of 380 r/min. Worn surface morphologies, phase and element compositions were studied by scanning electron microscope (SEM), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS), respectively. The mechanism of synergistic effect of CNTs and SiC nanoparticles was discussed. The results indicate that the AZ91D nanocomposites show better wear resistance properties and different wear mechanisms compared with AZ91D. The AZ91D nanocomposites reinforced with 0.5% CNTs and 0.5% nano-SiC have the best tribological capacity. The wear mechanisms for the Mg-based hybrid nanocomposites appear to be a mix-up of micro-ploughing, micro-cutting, slight adhesive wear and delamination.