Effect of Ball-milling Process on the Microstructure and Mechanical Properties of <i>In-situ</i> Synthesized Carbon Nanotube Reinforced Aluminum Composites

Abstract

Carbon nanotube (CNT) reinforced aluminum matrix composites were fabricated by powder metallurgy route, including in-situ chemical vapor deposition synthesis and ball-milling process. The effect of ball-milling process on the microstructure and mechanical properties of CNT/Al composites was investigated. The results show that the best tensile properties of CNT/Al composites can be achieved without adding any process control agent; with the increment of milling time, CNTs are gradually embedded into Al matrix and the composite microstructure becomes more dense and uniform. The hardness and tensile strength of CNT/Al composites continuously increase with the increase of milling time; however, the elongation firstly increases and then decreases. The composites after 90min of milling show a good balance between strength and ductility, and the hardness and tensile strength of which is 1.4 and 1.7 times higher than that of pure Al respectively, with elongation of 17.9%.

Keywords

• carbon nanotube
• mechanical property
• ball milling
• aluminium matrix composites