Influence of control and material parameters on regular eutectic growth and interlamellar spacing selection

All the parameters describing regular eutectic growth are split into two parts: set of control parameters and another of material ones. It is shown how two control parameters: v and G decide on interlamellar spacing lambda for the given set of material parameters. So, the significant influence of growth rate, v and slightly weaker of temperature gradient, G(x) are emphasized in the present analysis. The influence of G parameter is considered because it has been previously revealed experimentally. In the contradistinction to the models that take into account only thermodynamics of an interface present analysis adapts thermodynamics of whole investigated process. For that reason it becomes general and gives possibility to show the influence of both control parameters on the interlamellar spacing for imposed composition of an alloy. Thus, an attempt to reduce the suggested description to that given by Jackson-Hunt's theory is made. The influence of control parameters is shown by means of adequate growth law obtained using criterion of minimum entropy production. Moreover, the averaging of entropy production is modified. Additionally, definitions for coefficients of interplay between interface curvature and concentration field in the liquid for both regular and irregular structures are formulated in function of the partial derivative T/partial derivative x component of temperature gradient at the s/1 interface.