Fabrication and Properties of Magnesium Matrix Composite Reinforced by Carbon Nanotubes-Alumina Hybrid Reinforcements
Magnesium matrix composite reinforced by carbon nanotubes (CNTs)-Al2O3 hybrid reinforcements was successfully fabricated by a novel process. CNTs-Al2O3 in-situ mixture was synthesized by directly growing CNTs on Al2O3 particles acting as the carrier of Ni catalysts via chemical vapour deposition. The influences of Ni catalyst content on the morphology, structure and yield of CNTs were investigated. By powder metallurgy process, the CNTs-Al2O3 in-situ mixture was dispersed in Mg powder to fabricate the CNTs-Al2O3 synergistically reinforced Mg matrix composite. The performance test results showed that, the Mg matrix composite possessed improved mechanical properties, and the strengthening effects of CNTs-Al2O3 in-situ mixture were prior to those of single CNTs or Al2O3 reinforcement. The improvement of mechanical properties was due to that the introduction of Al2O3 can promote the dispersion of CNTs in Mg matrix and improve the interfacial bonding between CNTs and Mg.