Fabrication and Mechanical Properties of Aluminum Matrix Composites Reinforced with Carbon Nanotubes and Alumina

Abstract

The Al composites reinforced by carbon nanotubes (CNTs) and Al2O3 particles were fabricated by chemical vapor deposition (CVD) and ball milling method. The effect of milling time and Al2O3 content on the microstructure and mechanical properties of composites was studied. The results show that the uniform dispersion of CNTs and Al2O3 reinforcements in the Al matrix can be achieved by using this method. As the milling time increases, the microhardness of composite increases. When the milling time is 180min, the microhardness of composites reaches 2.1 times of pure Al. In addition, the microhardness and compressive yield stress of CNTs-Al2O3/Al composites both increase as the Al2O3 content increases. When the mass fraction of CNT reaches 4%, the microhardness and compressive yield stress of CNTs-Al2O3/Al composites are 112.1HV and 426MPa, which are the 2.8 and 4.6 times as large as that of pure Al, respectively. The results indicate that the hybrid addition of CNTs and Al2O3 play good synergic enhanced effect.

Keywords

• carbon nanotubes
• alumina
• ball milling
• Al matrix composite