Segregation of a nonvolatile impurity during normal freezing in an off-stoichiometric melt under constant component pressure

The effect of segregating a nonvolatile impurity during normal freezing in an off-stoichiometric melt under constant component pressure is examined. A modified normal freeze equation is derived relating the impurity concentration in the solid to the fraction of original melt solidified for any off-stoichiometric melt composition. The correction term in the modified equation becomes significant for segregation coefficients of the order of unity and melt compositions appreciably off stoichiometry. © 1965 The American Institute of Physics.