Ternary diffusion coefficients—Theoretical treatment and application to theIn-situ-reinforced TiB2/Al composite

Abstract

In the present work, a new model is developed to predict ternary diffusion coefficients in liquid state based on hard sphere theory and the Miedema model, and the diffusion coefficients are theoretically determined starting from the quantities of the pure component. Using this model, the diffusion coefficient of Ti in the TiB2/Al composite is evaluated and the influence of alloying element additions on the diffusion coefficient of Ti is discussed. The results indicate that additions of Si can promote the diffusion of Ti. Meanwhile, other elements including Cu, Fe, Mg, V, Ni, La, and Zr can hinder the diffusion of Ti. It is furthermore concluded that not only the phase diagram but also considerations concerning the kinetics are required to produce the desirable phases.