中文摘要：

利用化学镀法对MWCNTs镀银并通过高能球磨制备MWCNTs/Ag复合粉末，然后采用粉末冶金法制备MWCNTs增强Ag复合材料，利用扫描电镜对复合粉末的形貌以及复合材料中MWCNTs的分布进行分析，研究MWCNTs含量对MWCNTs/Ag复合材料力学性能的影响。结果表明：球磨后Ag颗粒聚集形成二次大颗粒，随着MWCNTs含量增加，颗粒聚集程度提高。MWCNTs体积分数达到10%后，MWCNTs/Ag复合材料中MWCNTs团聚严重；MWCNTs体积分数增大，复合材料强度、硬度先增大后减小，体积分数为8%时力学性能最佳，抗拉强度和屈服强度分别达到297MPa和245MPa，硬度HV0.1为80.1。复合材料表现出明显的塑性断裂特征，断裂面形成了较多的韧窝，且存在明显的MWCNTs拔出现象，说明MWCNTs起到载荷传递和增强作用。

英文摘要：

Multi-walled carbon nanotubes （MWCNTs） were coated by silver using chemical plating, MWCNTs/Ag composite powders were fabricated by high energy ball milling, and MWCNTs reinforced silver composites were obtained with powder metallurgy method. Morphologies of the composite powder and distribution of MWCNTs in the composite were analyzed by scanning electron microscopy. The effect of the MWCNTs content on the mechanical properties of the composites was studied. The results show that Ag particles gather to larger secondary particles after ball milling and the degree of aggregation increases with the increase of MWCNTs content. The MWCNTs present severe aggregation in the composites when the volume fraction of MWCNTs exceeds 10% （volume fraction）. With the increase of the volume fraction of MWCNTs, strength and hardness of the composite first increase and then decrease. The composite containing 8% MWCNTs exhibits optimal mechanical properties with tensile strength of 297 MPa, yield strength of 245 MPa, and hardness of 80.1 HV0.1. The MWCNTs/Ag composite shows obvious plastic fracture with many dimples on the fracture surface. Pull-out of the MWCNTs illustrates the load transferring and strengthening effect of MWCNTs.