EFFECT OF VACANCIES AND ALLOYING ORDERING ON THE THERMODYNAMICS DURING SOLIDIFICATION PROCESSING

The effect of the formation of a random distribution of elements and o f lattice defects in a solid during solidification processes on the th ermodynamics is discussed. The relationships describing the change in melting point and the composition of the solid phase from those in the equilibrium state are derived. The effect between different species a nd vacancies on the interaction is discussed. The derived models are u sed to illustrate the effect in some aluminium and copper based alloys . The models are also used to describe the formation of divacancies an d a short range ordered structure in the equilibrium state. The format ion of a compounds between vacancies and alloying elements are describ ed by the models.