图2. 定向凝固过程中枝晶竞争生长示意图^[19]

Fig.2. Schematic of dendrite growth illustrating the mechanism of competitive growth during directional solidification^[19] (θ—misorientation of the <100> cry-stallographic direction relative to the heat-flow direction. v—velocity, v_L—velocity of the liquidus isotherm, v_θ —growth velocity of dendrites with orientation θ. z—coordinate along the heat-flow direction. Δz₀, Δz_N, and Δz_θ —distances from the dendrite (or equiaxed grain) tip to the liquidus isotherm, for dendrite parallel to the heat-flow direction, for an equiaxed grain, and for dendrite at θ, respectively. ΔT—undercooling)