Shape Prediction of Ductile Iron Castings Consideration Furan Self-Hardening Sand Mold Deformation

Abstract

  In order to produce near-net shape castings, it is important to predict the final shape by taking into account thermal shrinkage during the solidification and cooling processes and thermal deformation caused by uneven cooling. In this study, to accurately predict the final shape of castings using numerical analysis, we proposed a simple calculation method that takes into account the deformation of the sand mold before the start of solidification. Calculations and verification experiments using this method were performed on rotor-shaped ductile iron castings, and it was confirmed that the prediction accuracy of the final shape was improved by taking into consideration sand mold deformation before the casting formed a solidified shell. Particularly with rotor shapes, the difference in the amount of deformation between the peaks and valleys was found to be smaller than the predicted difference assuming that cooling is uniform.