شبيه سازي اثر درصد Si در آلياژهاي AI-Si بر تغيير شكل دندريت و جريان مذاب بين دندريتي

Simulation of Percentage Si Effect on the Dendrite Shape and Inter-Dendritic Flow in the Solidification of Al-Si Alloys

In this investigation has been developed a numerical model for the determination of liquid flow permeability through columnar dendrite during solidification and growth based on the solution of Fickʹs equations. The model is inclusive two stages, first numerical evolution of the dendrite shape during growth (solidification) using a novel Cellular Automation Finite Difference method, and second numerical determination of flow pattern and fields of velocity and pressure near arms dendrites by a Computational Fluid Dynamic technique. Simulation results for Al-Si alloys shown, when increase Si, dendrite section morphology will change from cellular to cloverleaf shape. Therefore permeability of mushy zone could control of the micro-porosity and micro-shrinkage depended on the dendrite morphology. Also, experimental results shown, which exist a lot of micro-shrinkages in the inter-dendritic space for high %Si of the Al-Si alloys. Therefore the present code could be a good tool for predicting of the micro-shrinkage in the casting parts