한국주조공학회

The effects of pressure during solidification on macro-and micro-structures have been studied in pure aluminium and Al-Si alloys. The application of pressure during solidifcation accelerated both equiaxed and columnar dendritic-growth due to stimulating of equiaxed survival and faster preferential growth of primary dendrites against the parallel direction of heat flow. Burden-Hunt model was modified to express the significant changes of CET behaviours under pressure. A further point to be noted was that greatly fine eutectic silicon flakes (0.5x13μм) with the decrease of halo layers (7μм) of aluminium riched phases in the periphery of primary silicon particles were observed when pressure was applied during solidification.