The formation of dendritic equiaxed grain structure by heated mold technique has been investigated experimentally and numerically. The mathematical model has been developed to simulate the convection fields and temperature distributions. The model is implemented numerically for two-dimensional model problem with some similarities to the steel end chill casting process. The continuity equations for the mass, fluid flow and the energy have been solved and turned into practical scheme of computations by simpler method. An experimental work was conducted to study the thermal convection and directional solidification phenomena in horizontal rectangular cavity at different superheats. One aluminum alloy composition of Al-4.5%Cu alloy system were used. The model predictions were compared to the measurements where a good agreement was found. The variation of superheat that is known to influence on the convection streams and on the thermal fields was studied. The results indicate that the temperature gradient in the mushy and liquid zones play a major role to form dendritic equaxied structure. Furthermore, the metal heated mold is successful and practical technique to generate dendritic equaxied structure.
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