石墨含量对石墨/铝基自润滑复合材料摩擦性能的影响

Effect of graphite content on friction properties of graphite/aluminum matrix self-lubricating composites

利用选择性激光烧结（SLS）技术制备蜂窝结构石墨骨架,对蜂窝结构石墨骨架进行固化、浸渍、碳化和镀铜处理,制备蜂窝骨架结构石墨/铝基自润滑复合材料,并研究浸渍工艺和石墨含量对复合材料摩擦系数的影响。研究表明：浸渍工艺使石墨骨架中的孔隙明显减少,随着浸渍次数的增加,骨架中的固化树脂从断链状向网状和面状发展,有利于石墨骨架强度的提高,其中第一次浸渍强化效果最为显著;石墨的添加使复合材料的摩擦系数低于铝基体合金,但随着石墨含量的增加,复合材料稳定磨损阶段的摩擦系数先减少后增加,当石墨含量为10%时,摩擦系数最小,为0.3左右。

The honeycomb structured graphite skeleton was prepared by selective laser sintering（ SLS） technology,and then was cured,impregnated,carbonized and copper-plated,and finally the graphite/aluminum matrix self-lubricating composite was prepared. The effects of impregnation process and graphite content on friction coefficient of the composite were investigated. The results show that the porosity of graphite skeleton is obviously reduced by impregnation process. With the increase of impregnation times,the cured resin in the framework develops from broken chain-like to network-like and planar,which is beneficial to the improvement of graphite skeleton strength,and the strengthening effect of the first impregnation is the most remarkable. The friction coefficient of the composite is lower than that of the aluminum matrix alloy due to the addition of graphite,but with the increase of graphite content,the friction coefficient in steady wear stage of the composite decreases first and then increases. When the graphite content is 10%,the friction coefficient has the lowest value of 0.3.