The Effect of Air Gap between Casting and Water-Cooled Mold on Interface Heat Transfer Coefficient

Abstract:

Water-cooled casting is a new casting process. It allows even large castings to solidify rapidly, thereby reducing segregation and grain refinement. It has drawn the attention of both domestic and foreign businesses. Heat transfer at the casting/water-cooled mold interface controls the cooling rate of the casting. During the solidification process, because of the contraction that takes place during casting, an air gap can form between the casting and the water-cooled mold. This air gap hinders heat transfer between the casting and the mold, leading to a rapid drop in the interface heat transfer coefficient (IHTC). The purpose of the present study was to assess the effects of the width of the air gap and the duration of gap formation on IHTC. During the experiment, the casting temperature curve was determined in the presence of the interface air gap, and then inverse calculation was performed using PROCAST software to determine the IHTC of casting/water-cooled mold. Results showed that, after the formation of the air gap, IHTC first exhibited a rapid decrease, followed by an increase and then another decrease; IHTC was found to decrease as gap width increased and as the duration of gap formation increased.

• Periodical: Materials Science Forum (Volume 893)
• Pages: 174-180
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.893.174
• Online since: March 2017
• Authors: Yi Dan Zeng*, Qing Hu Yao, Xia Wang
• Keywords: Air Gap, Interface Heat Transfer Coefficient, Inverse, Water-Cooled Mold

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