【作者】 赵晓宏；

【导师】 崔春翔；

【作者基本信息】 河北工业大学 ， 材料学， 2002， 硕士

【摘要】 本文选用高强度、高模量的连续碳纤维作为增强相，与纯铜基体进行复合，试图获得高强度高导电的连续碳纤维增强铜基复合材料(C_f／Cu)。针对如何获得性能优异的C_f/Cu的制备工艺进行了试验研究，通过对复合材料的组织与性能及复合成型机理的研究和探讨，找出了影响复合材料综合性能的主要因素。 为了克服C_f／Cu制备过程中常见的纤维偏聚问题，作者采用对碳纤维两端施加预应力，制成碳纤维预型的方法可以有效控制液相浸渗成型时纤维在基体中的宏观分布均匀性。 本文采用阴极多点接触法，并用两步电镀铜代替普通的酸性硫酸盐镀铜，对经热氧化预处理后的碳纤维进行表面处理来改善碳纤维与铜基体之间的润湿性，可以有效的提高电流效率，可以获得镀层均匀连续、镀层与纤维之间结合牢固的碳纤维镀铜复合丝，消除了黑心和镀铜不连续现象，并保证了在随后的复合过程中复合丝与铜基体之间良好的复合性能。 采用真空熔融浸渗成型法制备C_f／Cu，并在熔融浸渗成型的过程中通入惰性保护性气体，与普通的液相浸渗成型法相比，有效的改善了铜液相对预型的添充能力，消除了普通熔铸法产生的严重填充不足现象，并避免了压力浸渍法产生的高压对纤维的严重损伤造成的纤维性能受损。真空态及惰性气体的加入不但优化了复合材料成型时的外界气氛、促进了润湿，而且还有利于熔炼及成型过程中杂质气体的排除。真空熔炼浸渗，铜液相对纤维预型的填充效果好，铸造缺陷大幅减少，纤维损伤及断裂的得到很大程度的减弱，改善了C_f/Cu的综合性能。 本文对C_f／Cu复合成型过程的数学模型进行探讨，并提出了影响复合材料复合成型的主要因素。通过观察和分析复合材料的微观组织分布，作者认为复合材料成型过程可以用两种理想形核长大模型来描述。模型一：基体液相内部形核，推移纤维长大模型；模型二：沿纤维表面非自发形核，沿纤维长大模型。 实验测定了C_f／Cu的导电率和平行于纤维排布方向的拉伸强度，并对C_f／Cu的断裂机理及复合材料导电性的影响因素进行了探讨。更多还原

【Abstract】 In this thesis continuous fibers with high strength and high module was compounded with copper matrix to acquire continuous carbon fibers reinforced copper matrix composite (Cf/Cu) with high strength and high conductivity. Study on fabricating technology to acquire good properties, through discussing the relative between microstructure and properties, the mechanism of infiltrating and molding, we presented the main factors effect on the synthesis properties of Cf/Cu.To cope with the usual problem of fiber gathering during fabricating carbon fiber reinforced copper matrix composites, the author of this thesis exerted prestress along fibers in fiber premodel, which can control the uniformity of fiber distribution in matrix effectively during copper liquid infiltrating the fiber premodel.To improve the wetting quality between the fiber and the copper matrix, plated copper on fibers after oxidation in hot air by two steps methods instead of usual method including CuSO4 and H2SO4, and connected cathode on several spot. To increase the efficiency of electrical current and gain even and continuous copper coating, and the black core phenomena disappeared, and the bonding between copper coating and fiber became better assuring the good compositing characteristic in the following fabricating of Cf/Cu.Fabricated Cf/Cu through melt and infiltration in vacuum, and aerated inert gas in the course of melt and infiltration. Compared with general infiltration, the infiltration in vacuum can improve the filling ability of copper liquid to fiber premodel, and avoid the serious inadequate filling in usual casting, and avert the fiber quality damage following high pressure during infiltration under pressure. Vacuum condition and the adding of inert air not only optimized the outer atmosphere and improved the wetting quality, also avail to get rid of the impure gas during the course of melt and infiltration. Through melt and infiltration in vacuum, copper liquid can obtain good filling effect to fiber premodel, ihe casting defection was decreased markedly, and the damage and -fracture of fibers was deadened, and the synthetically properties of Cf/Cu were improved remarkably.In this thesis the maths model of the compositing of C/Cu was discussed and the main factors which affected on the quality of moulding. Through observing and analyzing the microstructure of C/Cu, the author considers that we can describe the moulding course by two academic model. Model one is produce crystal nucleolus inside copper matrix and grow by pushing fibers, and Model produce crystal nucleolus along fibers and grow unspontaneously along fibers.Through experiments measured the conductivity and the extruding strength along the direction parallel to fibers, and probed in the mechanism of fracture of C/Cu , and discussed the influential factors to the conductivity of C/Cu.更多还原