Mechanical Properties of Nano SiC Reinforced Aluminum 7075-T6 Produced by Warm Powder Compaction using an Inert Gas

Abstract

The micron-sized Al7075powder reinforced with nano-sized SiC particles is compacted at 400⁰C in an inert atmosphere using Nitrogen. It is shown that this technique can significantly improve the mechanical properties of the compacted powder characterized by measuring hardness, stress-strain curves and density. The maximum relative density was %98.8 and obtained for 2.3 GPa pressure and 0%SiC content. The minimum density was %93.95 and was obtained for 10%SiC content and 1.3 GPa pressure. The degree of porosity and the number and size of the void decreased as the compaction pressure increased and increased with the increase of SiC volume fraction. The maximum increase in ultimate strength was about 72% and occurred for the 5%SiC content and the 1.3 GPa compaction pressure. For 10%SiC volume fraction the strength improved by 53% for 2.6 GPa pressure. The effect of SiC content on ultimate strength was significantly higher than that of the compaction pressure. The maximum increase in Vickers hardness of the compacts was 100% and obtained for the samples with 10%SiC volume fraction and compacted at 2.6 GPa pressure. Again, the effect of SiC volume fraction on hardness improvement was found to be remarkably greater than that of compaction pressure.