The effect of the processing technique on the microstructural and mechanical characteristics of A319/SiCp metal matrix composites (MMCs) was investigated. Composites containing 15 vol.-% of SiC particulates were fabricated using two different variations of rheocasting technique namely semi-solid (SS) and semi-liquid (SL) techniques. Tensile tests were conducted to evaluate the performance of the prepared alloys. Microstructural observations showed that the processing technique has a great influence on the morphology of -Al and eutectic silicon as well as the porosity content. The composites showed acceleration in the precipitation kinetics in comparison with the unreinforced materials. Moreover, the SS composites showed also acceleration in the precipitation kinetics when compared with SL composites. The tensile tests results revealed that SS composites have better ultimate and yield strengths when compared with SL composites. |
