| Popis: |
In traditional casting, sand is used as a mould material to carry heat away from the melt. However, sand has certain disadvantages, such as poor thermal conductivity, burning of binders, undesirable transition resulting in mould failure, and defects in the components. To overcome these limitations, magnetic moulding technology was introduced more than a few decades ago, but the process never achieved the required industrial developments to commercialise this technology. It is essential to reconsider and develop this technology further to use it as a regular production process. In this paper, processing of Al/SiCp composite using magnetic moulding technology is discussed. The heat transfer results of magnetic moulding process are simulated using COMSOL Multiphysics software and compared with the sand casting process. The temperature distribution, thermal conductivity, and phase change have been studied, finding that steel shots as mould materials show better heat transfer results when compared with sand. This better heat transfer led to a decrease in solidification time by 25%, which in turn improved the hardness (by 70%), impact toughness (by 4 times), and wear resistance (by 42%) of the Al/SiCp cast produced. These results very clearly illustrate the unique signature of the magnetic moulding process. |
