【摘要】 以添加碳化硼的炭纤维针刺整体毡为预制体,经化学气相渗透以及树脂浸渍/炭化混合增密制备含碳化硼C/C复合材料,通过MM-1000型摩擦磨损试验机并结合摩擦表面和磨屑形貌的扫描电子显微镜观察分析,研究了热处理温度(2 000℃、2 300℃和2 500℃)对含碳化硼C/C复合材料摩擦磨损性能的影响.结果表明:在2 000℃时,含碳化硼C/C复合材料呈现出磨粒磨损特征,其磨损相当严重,摩擦系数较高,摩擦力拒曲线翘尾严重;在2 300℃时,碳化硼发挥了促进石墨化的作用,使得含碳化硼C/C复合材料的石墨化度提高,在摩擦过程中摩擦表面能够形成平整而光滑的自润滑膜,材料耐磨能力明显增强,摩擦系数略有下降,制动过程平稳;在2 500℃时,含碳化硼C/C复合材料的石墨化度提高至97.8%,与2 300℃时相比,其摩擦系数和磨损量具有一定程度的增加,摩擦力矩曲线抖动加剧.更多还原

【Abstract】 C/C composites with B₄C additive were prepared by chemical vapor infiltration and followed by resin impregnation/carbonization process with integrity felts with B₄C additive.The tribological properties of the composites treated at 2 000 ℃,2 300 ℃ and 2 500 ℃ respectively were investigated on an MM-1000 friction tester.For the composites treated at 2 000 ℃, the worn mechanism was grain-abrasion.The composites exhibited very severe abrasion and higher friction coefficient,and with obvious turnup tail in braking curve.For the composites treated at 2 300 ℃,boron carbide resulted in catalyze graphitization remarkably and the composites exhibited higher graphitization degree,smooth lubrication film was formed at worn surface,thus the composites exhibited very good abrasive resistance,lower friction coefficient and stable braking property.However,for the composites treated at 2 500 ℃,the graphitization degree was up to 97.8%,as a result,the abrasion and friction coefficient increased compared with those at 2 300 ℃,and braking curve exhibited violent fremitus.更多还原