纳米ZnO/环氧树脂复合材料的力学性能和摩擦学性能

Tribological and Mechanical Properties of Nano ZnO-Filled Epoxy Resin Composites

在超声波作用下,利用偶联剂将ZnO纳米微粒同环氧树脂进行复合,制备了纳米ZnO/环氧树脂复合材料,用M-2000型摩擦磨损试验机评价了复合材料在干摩擦条件下同不锈钢对摩时的摩擦学性能,测定了复合材料的力学性能,并用正电子湮没寿命技术(PALT)分析了试样的微观结构.结果表明:纳米ZnO/环氧树脂复合材料的耐磨性优于环氧树脂;当纳米ZnO的质量分数为10%时,复合材料的磨损率最小,仅为环氧树脂的15%,且摩擦系数也有所降低;摩擦后复合材料试样的自由体积孔穴尺寸有所增大,而且随着ZnO含量的增加,自由体积孔穴尺寸呈增大趋势.

Epoxy resin composites filled with nano ZnO particulates were prepared by proper curing, using KH-560 silane coupling agent to enhance the interfacial bonding between the inorganic reinforcing agent and the polymer matrix in the presence of ultrasonic agitation. The mechanical properties of the resulting composites were measured, while their friction and wear behaviors under dry sliding against a stainless steel were examined on an M-2000 friction and wear tester. Moreover, the effect of friction on the microstructure of the composites was investigated based on the analysis of the free volume features of the composites by means of positron annihilation lifetime spectroscopy (PALS). As a result, the filled epoxy resin composites showed better wear resistance than the epoxy resin matrix, and the composite filled with 10% ZnO had the smallest wear rate. This was attributed to the strengthening function of the nanometer particulate filler which was well bonded to the polymer matrix in the presence of the coupling agent. Friction led to an increase in the free volume hole size of the composites, while the average size of free volume holes tended to increase with the increase of ZnO content.