熔渗法制备C/C-Cu复合材料的力学性能

以炭纤维(Cf)针刺整体毡为预制体,分别采用化学气相渗透(Chemical vapor deposition,CVI)和浸渍炭化(Impregnation and carbonization,I/C)制备不同密度和基体炭的C/C坯体；通过添加Ti元素改善熔融Cu与C/C坯体的润湿性.采用真空熔渗法制备C/C-Cu复合材料.对复合材料的力学性能及其与坯体之间的关系进行研究,并与常用滑板材料的力学性能进行比较.结果表明:随着坯体密度的增加,复合材料的抗弯强度下降,而坯体密度为1.4 g/cm3的复合材料的冲击韧性达到最大值.与用I/C坯体制备的复合材料相比,用CVI坯体制备的复合材料具有更高的强度和韧性,其弯曲曲线呈“假塑性”断裂特征,断裂时纤维从热解炭层或熔渗金属相中拔出,熔渗金属相呈“韧窝状”的塑性断裂形貌.冲击断裂时,复合材料倾向于沿TiC/熔渗金属界面断裂.C/C-Cu复合材料的抗弯强度为180～300 MPa、冲击韧性高于3.5 J/cm2,优于常用滑动电接触材料的性能,是一种极具潜力的新型滑动电接触材料.

Mechanical properties of C/C-Cu composites fabricated by molten infiltration method

Using Ti addition to improve the wettability between the molten copper and C/C preforms,C/C-Cu composites were fabricated by infiltrating molten copper to C/C preforms with different densities and matrix carbon types,which were prepared by chemical vapor deposition(CVI) or resin impregnation and carbonization(I/C).The mechanical properties of the composites and the relationship between the properties and preforms were studied.The mechanical properties were compared with those of the widely used sliding elec...