AN INVESTIGATION OF MICROSTRUCTURE AND WEAR PROPERTIES OF AL-TI MATRIX COMPOSITES REINFORCED WITH SIC AND AL2O3 PARTICLES

In this research, the production of Aluminum matrix composites (AMCS) consolidated by hot powder extrusion along with physical and mechanical properties of extruded bars have been studied. The matrix alloy was prepared from elemental powders of Al and 10wt% Ti. The composites comprises 5, 10, 15 or 20 vol% SiC or Al2O3 particles with an average size of 5 micron. The powder mixtures were sealed in an aluminum cans and then hot extruded in 600 C. Ram speed and reduction ratio were 72 mm/min and 10:1 respectively. The examination of the composite microstructures has generally shown that the ceramic particles of SiC and Al2O3 are uniformly distributed in the matrix. XRD analyses showed that as-extruded specimens containing Ti alloying element consisted of Al3Ti inter metallic compounds. The obtained composites containing inter metallic compounds or ceramic reinforcements showed better wear resistance and micro hardness but lower ductility than pure Al.