Characterization of Aluminium Metal Matrix Composites with TiB2 Reinforcement by STIR Cast Method

Abstract

In recent years Aluminium (Al)/Titanium di Boride (TiB2) composites fabricated by in-situ technique have received more attention due to their better mechanical properties and their high specific strength to weight ratio. newlineThe aim of the present work is to develop Al-2011/TiB2 (5, 10 wt %) composites by in-situ method using the mixture of Potassium Hexafluro Titanate (K2TiF6) and Potassium Tetrafluro Borate (KBF4) halide salts. In order to improve the uniform distribution of particles and mechanical properties of the composites, secondary process of direct extrusion is carried out to improve the metallurgical and mechanical properties of the composites. Further, newlineas-cast and extruded billets are heat treated for solutionizing temperature at 510and#9702;C to obtain newlineoptimum strength. Then ageing is carried out at 160and#9702;C for 15 hrs. The heat treatment of the Al/5wt % TiB2 and Al/10wt % TiB2 samples of as-cast, and extruded composites can improve the strength of the samples. newlineThe surface morphology of the Al/5wt % TiB2 and Al/10wt % TiB2 samples in as-cast, heat treated and extruded conditions are investigated by Scanning Electron Microscope (SEM), Energy Dispersive X-ray Analysis (EDAX) and X-Ray Diffraction (XRD). TiB2 and the intermetallic compound formed in the composites are observed through SEM images and conformed by EDAX and XRD studies. newlineThe hardness of Al/5wt % TiB2 and Al/10wt % TiB2 samples in as-cast, heat treated and extruded conditions are studied by Vickers hardness test. The result revealed that extruded and heat treated Al/10wt % TiB2 samples show better hardness values than the other samples. newlineThe tensile strength of Al/5wt % TiB2 and Al/10wt % TiB2 samples in as-cast, heat treated and extruded conditions are investigated by Universal Testing Machine (UTM) with maximum load rating of 400kN. The result showed that samples made up of the extruded composites that are subject to heat treatment showed improvement in this mechanical property. newlineThe corrosion behavior of Al/5wt % TiB2 and Al/10wt % TiB2 samples in a