Journal of Material Sciences & Engineering

Fabrication of Functionally Graded Carbon Nanotube-Reinforced Aluminium Matrix Laminate by Mechanical Powder Metallurgy Technique - Part I

Abstract

Udupa G, Rao SS and Gangadharan KV

Advances in material science have led to innovation of new materials having different properties. Functionally Graded Laminates (FGL) belong to this trend. In this work, an attempt has been made to fabricate Functionally Graded Carbon Nano Tube (CNT) reinforced Aluminium matrix laminates by an innovative powder metallurgy based cold compaction technique. The FGL composites have been prepared by incorporating CNT particles to aluminium metal matrix in different weight fractions, ranging from 0.1 to 0.5 wt%. The mechanical properties of these FGL composites have been studied in detail for assessing the effectiveness of the adopted fabrication technique. This method is an effective way to change the properties of the materials as required in different directions. The gradient layers here exhibited different microstructures and variation in hardness from one end to the other. Absence of Aluminium Carbide in the FGL composites is an important finding of this work highlighting the chemical stability of CNT in Al-matrix. An increase in the hardness by 129% was observed in the case of 0.5 wt.% of CNT in the formed laminates. Each layer demonstrated good adhesion after sintering process with no serious pores or microcracks.