Movement of grain boundaries in pure and boron-doped Ni 3Al polycrystals

Abstract

Using Mishins' et al. theory [2], diffusion penetration profiles obtained in a previous paper [1] were reevaluated in order to obtain information on the influence of chemical composition on the GB mobility in Ni 3Al polycrystals. It was obtained that, for identically treated alloys, the addition of boron lowers the mean velocity of GB motion but, at the same time, it increases the fraction of moving GBs. The activation energies of GB diffusion in transverse and in parallel direction to GBs are equal within experimental errors.