ALUMINIUM BASED COMPOSITE FOR STRUCTURAL APPLICATION

Abstract

Aluminium is extensively used for structural applications as aerospace, automotive, marine, civil applications due to its superior specific properties like, high strength to weight ratio, high corrosion resistance. But aluminium poses low strength, which can be improved by suitable reinforcing material like graphene. Graphene has single layer honeycomb structure having high elastic modulus of ~1TPa and strength of ~130 GPa. The high surface area of Graphene results in good bonding with aluminium matrix and effective load transfer from matrix, which improves strength of aluminium. In the present study, aluminium matrix composite reinforced with 0.5, 1, 3, 5wt% of Graphene oxide (GO) prepared by spark plasma sintering at constant pressure of 50 MPa and 550°C holding temperature at the heating rate of 110°C /min. The Graphene oxide (GO) was synthesised by modified Hummer’s method. A pure aluminium sample was also fabricated through same processing route for the comparison of mechanical properties and characteristics. The structural characteristics were studied through XRD, optical and SEM analysis. The mechanical properties were studied through Vicker’s hardness and tensile test. A relative density of ~99% was achieved for all sintered composites. Composite with 0.5wt% GO results highest improvement in hardness (11.46%) and tensile strength (44.57%) w.r.t. pure aluminium, due to uniform dispersion of GO within matrix and effective load sharing properties. The fracture surface was also analysed by SEM analysis.