钢纤维对铜基金属陶瓷摩擦材料力学和摩擦学性能的影响

研究了钢纤维含量及长径比对汽车离合器用Cu基金属陶瓷摩擦材料硬度、力学性能及摩擦磨损性能的影响．结果表明,钢纤维同Cu基体结合良好,钢纤维可增加金属陶瓷的硬度和弯曲强度;钢纤维含量及长径比对Cu基金属陶瓷摩擦材料的摩擦磨损性能具有明显影响;随着钢纤维含量和长径比的增大,摩擦系数对比压的敏感性减弱;当钢纤维含量为10％～30％时,长径比较大的SF-1钢纤维增强Cu基金属陶瓷摩擦材料的综合摩擦磨损性能较优,相应的偶件磨损较轻微．

Influence of Steel Fiber on Mechanic and Tribological Properties of Cu-Based Cermet Friction Material

Cu-based friction materials reinforced with steel fibers of different ratios of, length-to-diameter ratios were prepared making use of powder metallurgy. The surfaces and cross-sections of the resulting friction materials were observed on a scanning electron microscope. The mechanic properties of the friction materials were measured, while their friction and wear behaviors sliding against cast iron counterparts were evaluated on an MM-1000 friction and wear tester. It was found that the reinforcement with the steel fibers led to an increase in the hardness and bend strength of the friction materials, and the friction and wear behaviors of the steel fiber reinforced Cu-based friction materials were highly dependent on the mass fraction and length-to-diameter ratio of the steel fibers. Namely, the friction material reinforced with the steel fiber of a larger length-to-diameter ratio and mass fraction had a larger and more stable friction coefficient with varying specific braking pressure, i.e., the friction coefficients in this case were less sensitive to the specific braking pressure. In terms of the optimized comprehensive tribological behaviors, the cermets reinforced with the SF-1 steel fiber of a larger length-to-diameter ratio were superior to those reinforced with the other two kinds of steel fibers, and the corresponding cast iron counterpart had a smaller wear as well.