Apparent Growth Direction of Primary Dendrites in Chill Zone

Abstract

Apparent growth directions of dendrites in the initial solidification zone have been analyzed theoretically and experimentally. In a 2-D observation, the dendrite trunk can be observed as a projection to an observing cross section. Thus, the angle between heat flow direction and projected trunk may be lower than the real angle. In order to predict the distribution of apparent angle of dendrite trunks, a simple physical model has been developed and statistically analyzed. According to this model, dendrite trunks, the growth directions of which are close to the heat flow direction, become larger than the other. This prediction agrees well qualitatively with the experimental result which was carried out using SUS304.