Cooling rate and graphite structure of final eutectic solidification part in cast iron

Abstract

A CE meter cup was modeled using a casting simulation software and cooling curves at different points of the casting model were calculated. In setting temp-solid fraction parameters, an Fe-C-Si ternary equilibrium phase diagram was used with a substantive temperature range in the equilibrium phases so that the γ-Fe+G+L phases can be considered. In studying the calculated cooling curve, a rapid temperature drop was found in the cooling curve in the final solidification period. This rapid cooling occurred during eutectic solidification. The structure formed by the rapid cooling was found as chill or D-type graphite because the liquid phase is cooled rapidly to below the eutectic temperature. This rapid cooling may be one of the causes of D-type graphite near the final solidification part of thick iron castings. © 2011 Japan Foundry Engineering Society.