Synthesis and properties of Al-AlN-CuCNT and Al-Y2W3O12-CuCNT hybrid composites

Abstract

The effect of the addition of various amounts (1, 2 and 4 wt%) of copper-coated multi walled carbon nanotubes (CuCNT) on the mechanical (hardness, compressive strength and elastic modulus) and thermal (thermal conductivity and coefficient of thermal expansion) properties of two sets of aluminium matrix hybrid composites (AMHCs), i.e., Al- 30 wt % AlN and Al-30 wt % Y2W3O12 has been investigated. The CNTs and AMHCs are fabricated using the molecular-level mixing and powder metallurgy route, respectively. The TEM analysis reveals that the CNTs are effectively coated with copper. The SEM characterization reveals that the CuCNTs are uniformly dispersed in the aluminium matrix. Experimental results reveal that the addition of CuCNT into the AMHCs increases the hardness, compressive strength, elastic modulus and thermal conductivity. Dilatometry studies reveal that the thermal stability of both the AMHCs increases with an increase in the amount of CuCNT as well as the number of thermal cycles. The coefficient of thermal expansion also decreases significantly with an increase in the amount of CuCNT in both the AMHCs.