The cooling rate, mechanical Strength and DAS(Dendrite Arm Spacing) were investigated for aluminum platecastings (AC4B) with square column and round-column thathave the same shaped core, and for plate castings. The resultsshowed that when the core size decreased, thereby increasing thevolume to surface area ratio (V/S), the cooling rate also decreased.The mechanical strength decreased with increasing V/S, but DASincreased with increasing V/S. The solidification time of AC4Bsquare column castings and plate castings was proportional to thenth power of the modulus(V/S): tf=A(V/S)n, where n=1.6 for thesquare column castings, and n=1.4 for the plate castings. Thefollowing relationships (in-line logarithms) were found formechanical Tensile strength σB=K1(V/S)-n Brinell hardness,HB=K2(V/S)-n, and DAS,Ds=B(V/S)n.
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