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研究含石墨(Gr)和氮化硅纳米颗粒金属型搅拌铸造LM16合金的摩擦学性能。在干滑动摩擦条件下分别制备Al-Gr-Si_3N_4混杂复合材料、Al-Si_3N_4和Al-Gr纳米复合材料。采用EDS测试技术确保Si_3N_4纳米颗粒和石墨在铸件中的均匀分布。采用L9正交实验方法进行实验以研究应用载荷(20,30和40 N)和滑动距离(1,2和3 km)对合金摩擦磨损性能的影响。结果表明:与Al-Si_3N_4纳米复合材料相比,Al-Gr-Si_3N_4混杂复合材料的磨损率和摩擦因数(COF)分别降低了25%和15%,而Al-Gr纳米复合材料的磨损率和COF很小。混杂复合材料的显微维氏硬度比普通复合材料的提高了14%,而Al-Gr和Al-Si_3N_4纳米复合材料的显微硬度无明显变化。用扫描电镜对合金磨损表面和次表面的组织进行观察。结果表明,纳米复合材料的主要磨损机理为磨粒磨损,而混杂复合材料的主要磨损机理为磨粒磨损和粘着磨损。方差分析(AVOVA)和F检验用于验证模型的有效性及确定影响磨损率的显著性参数。
The tribological properties of LM16 alloy with graphite (Gr) and silicon nitride nano-particles were studied. Al-Gr-Si_3N_4 hybrid composites, Al-Si_3N_4 and Al-Gr nanocomposites were prepared under dry sliding friction conditions. The EDS test technology is used to ensure uniform distribution of Si 3 N 4 nanoparticles and graphite in the casting. The L9 orthogonal experiment was used to study the effect of applied load (20, 30 and 40 N) and sliding distance (1, 2 and 3 km) on the friction and wear properties of the alloy. The results show that the wear rate and friction coefficient (COF) of Al-Gr-Si_3N_4 hybrid composites are reduced by 25% and 15%, respectively, compared with that of Al-Si_3N_4 nanocomposites. However, COF is small. The micro-Vickers hardness of the hybrid composites increased by 14% compared with that of the common composites, while the microhardness of Al-Gr and Al-Si_3N_4 nanocomposites did not change significantly. Scanning electron microscope (SEM) was used to observe the microstructure of wear surface and subsurface of the alloy. The results show that the main wear mechanism of nanocomposites is abrasive wear, while the main wear mechanism of hybrid composites is abrasive wear and adhesive wear. Variance analysis (AVOVA) and F-test were used to verify the validity of the model and determine the significant parameters that affect the rate of wear.