Synthesis and cold workability behavior of al sic y2o3 hybrid nano composites produced through pm

Abstract

The present research work involves synthesis and workability behaviour of Al-SiC-Y2O3hybrid metal matrix composites and its multi objective optimization of cold upsetting parameters. he Aluminium metal matrix composites were produced by using SiC and Yttria as reinforcement particles through powder metallurgy with aspect ratio of 0.9 and 1.2. In this research work, two SiC particle sizes were used, namely, 60and#956;m and 80and#956;m. The weight percentage of SiC varied from 0 to 20 % with an interval of 4 %. The particle size of yttria is 30-50nm and the weight percentage of yttrium oxide varied from 1%, to 3% in steps of 1%. The characterization of Al-SiC-Yttria composites was carried out using Energy dispersive X-ray spectroscopy analysis, X-ray Diffraction analysis and Scanning electron microscopy. The study of cold upsetting behaviour of pure Aluminium and Al-SiC-Y2O3 hybrid nano composites showed that the effective stress is higher than the axial, hoop and mean or hydrostatic stresses under tri-axial stress state condition. The tri-axial stresses increase with increase in reinforcement particles and decrease with aspect ratio. The reason for increase in tri-axial stresses, is due to better densification and decrease in pore bed height. The effect of reinforcement particles on the formability stress index value was studied. The formability stress index increases throughout plastic deformation for addition of reinforcement particles. The reason is that, as the SiC and Yttria content increases, the relative density also increases and porosity level decreases. Formability stress index increases with decrease in aspect ratio as well as SiC particle size newline