Development and mechanical characterisation of Al-4.5%Cu alloy prepared using spark plasma sintered method

Abstract

Spark plasma sintering of Al-Cu composites yields a refined low segregation microstructure and the conversion of spherical grains to irregular non-dendritic structures during the cooling phase of the process. Al-4.5Cu alloy powder with an average particle size of 210 to 250 µm was gas atomised in an inert gas for physical and mechanical characterisations. The alloy powder was compacted into cylindrical specimens of 30 mm diameter and 20 mm thickness. The Al-4.5 wt. % Cu alloy powder was filled in enclosed graphite die and with the application of pressure and heat, the sintering samples were developed. For microstructural characterisation and mechanical properties, test samples were prepared by using Electrical discharge machining wire-cutting machine according to ASTM standards. The density of the alloy was improved in the range of 4.7% to 7.8% and the hardness value was improved by more than 100% when compared to the conventionally sintered Al-4.5Cu alloy. The compressive strength of the spark plasma sintered alloy is much higher than the conventionally sintered alloy samples by 307.32%, 150.15% and 47.45%.