Abstract

In this paper, the effects of Cu coating of carbon nanotube (CNTs) as reinforcement on structural, microstructural, physical and mechanical properties of Cu–3 wt%CNT nanocomposite were investigated. CNTs were coated by Cu using the electroless technique for 1 and 2 h. Bulk nanocomposite samples were produced by spark plasma sintering of a mechanically milled powder mixture of Cu and CNT. Kinetic study showed a nucleation and growth mechanism for the Cu coating process. Microstructural characterization showed that the coated CNTs dispersed more homogeneously in the powder mixture. Results also revealed that 1 h coating of CNTs led to the higher relative density and thermal properties. The coating process increased 62 Brinell hardness (BHN) in hardness, 14% IACS in electrical conductivity for Cu–CNT nanocomposite. Transmission electron microscopy analysis showed a strong bonding between CNT and Cu matrix within the distinguishable interface. About 20 MPa increase in shear strength of nanocomposite was observed by 1 h coating of CNTs. Also, the fracture surfaces exhibit changes in the mode of fracture by well-bonded CNTs with the Cu matrix. The coefficient of thermal expansion and thermal distortion parameter revealed 12.7 ppm/k and 0.037 ppm.m/w for the sample including 1 h coated CNT, respectively.

Graphic Abstract

中文翻译：

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铜和铜包覆碳纳米管的火花等离子体烧结制备高性能铜基纳米复合材料

摘要

在本文中，研究了碳纳米管（CNT）的铜涂层作为增强剂对Cu-3 wt％CNT纳米复合材料的结构，微结构，物理和机械性能的影响。使用化学镀铜将CNT涂覆1小时和2小时。通过火花等离子烧结机械研磨的Cu和CNT的粉末混合物，可以制备出大量的纳米复合材料样品。动力学研究表明铜包覆过程的成核和生长机理。微观结构表征表明，涂覆的CNT在粉末混合物中更均匀地分散。结果还表明，CNT的1 h涂层导致较高的相对密度和热性能。对于Cu–CNT纳米复合材料，涂层工艺的硬度提高了62布氏硬度（BHN），电导率提高了14％IACS。透射电子显微镜分析表明，在可分辨的界面内，CNT和Cu基体之间有牢固的结合。通过涂覆CNT 1小时，观察到纳米复合材料的剪切强度提高了约20 MPa。而且，断裂表面通过与铜基体的良好结合的CNT表现出断裂模式的变化。对于包括1小时涂覆的CNT的样品，热膨胀系数和热变形参数分别显示为12.7ppm / k和0.037ppm.m / w。

图形摘要