奈米碳管強化鋁基複合材料之機械性質研究

Mechanical Properties of Carbon Nanotube Reinforced Aluminum Composite

張智評(Z. P. Chang) ； 康永昌(Y. C. Kang) ； 陳立業(S. L. I. Chan)

《材料科學與工程》 36卷2期 (2004/06) Pp. 98-105

https://doi.org/10.6409/JMSE.200406.0098

摘要

本研究探討以奈米碳管作為強化相，對鋁基複合材料在室溫拉伸與硬度等機械性質之影響。首先以電弧放電法製備出奈米碳管，並以液相氧化法純化碳管，消除大部分雜質。純化後的碳管利用粉末冶金法添加於純鋁基地中，製成含奈米碳管的複合材料。實驗發現添加1wt.%未純化碳管為強化相的鋁基複材，其拉伸強度反而比母材降低。因未純化的碳管含有不少的石墨，而石墨本身強度較低，且和鋁基材界面的潤濕性不佳，導致石墨粒子劈裂或界面脫離。若添加1wt.%純化後碳管為強化相的複材，其拉伸強度則大幅提伸，甚至超越添加10wt.%微米級碳化矽為強化相的複材。證實所添加的奈米碳管確實具有極優秀的強化效果。

關鍵字

電弧、奈米碳管、複合材料

並列摘要

In this study, the feasibility of using carbon nanotubes (CNTs) as a reinforcement in Al matrix composites has been investigated. CNTs were produced by arc-discharge. After liquid phase purification, impurities such as graphite can largely be eliminated, leaving CNTs as well as carbon nano-particles in the nano-powder. In the production of composite via powder metallurgy route, wet mixing of the Al powder and nano-powder was adopted to avoid agglomeration of the nano-powder. After cold isostatic pressing, vacuum sintering and extrusion, CNT-reinforced aluminum composites with a density close to the theoretical value was obtained. It was found that the addition of 1 wt% as-produced nano-powder in the composite lowered the tensile strength of the composite, which can be attributed to two reasons. The large graphite particles in the nano- powder acted as stress concentration sites under tensile stress. In addition, the wetting between the matrix and the graphite was poor, causing the graphite particles to cleave or break away from the matrix. All these were detrimental to the mechanical properties of the composite. However, if the nano-powder was purified, the tensile strength was largely enhanced. With only 1wt% of purified CNTs added as reinforcement, the tensile properties of the composite was even higher than those of a composite reinforced with 10 wt% of micrometric SiC. In summary, our study shows that CNTs have a superior strengthening effect in Al-MMC.

並列關鍵字

arc discharge ； carbon nanotubes ； aluminum matrix composite