Uniformly dispersion of carbon nanotube in aluminum powders by wet shake-mixing approach

Abstract

Since its discovery, carbon nanotube (CNT) was proposed as an ideal reinforcement material for metal matrix composite for its high strength, excellent electrical and thermal conductivity. CNT reinforced aluminum matrix composite has attracted most attention at the beginning of 21st century due to the need for advanced lightweight alloys for aerospace, automotive and defense industries. However, few researchers have successfully incorporated pristine and undamaged CNT into matrix to enhance the properties of the composite. Both traditional and novel powder metallurgical routes have been explored, nevertheless, challenges like the poor distribution of CNT in Al matrix, the agglomeration of CNTs and the damage of essential CNT tubular structure impeded the full translation of CNT potential into various matrix. To achieve a uniform dispersion of CNT without damaging the CNT structure, the authors have applied a novel wet shake-mixing method which combined the advantages of ultrasonication, turbular mixing and ball milling to fabricate an homogenous Al–0.5wt.% multi-walled carbon nanotube (MWNT) composite. The original structure and morphology of MWNTs and aluminum powders were well preserved even after all the processing procedures in the as-produced powders. This is confirmed by scanning electron microscopy and X-ray diffraction analysis, particle size distribution and the Raman spectra of the as-produced composite powders.