7. Solidification and segregation coefficient

During cooling, liquid solidification begins at the temperature of intersection of the vertical line drawn on the alloy composition x ₀ diagram with the liquidus line (figure 18 ). When only a single solid phase is formed, the composition of the first crystals can be read on the diagram at the intersection of the horizontal isotherm at the start of solidification with the solidus line. As solidification continues, the temperature falls, the composition of the liquid follows the liquidus and that of the solid the solidus. In the case of figure 18 both phases in equilibrium become simultaneously enriched in element B, but through...