Particle pinning force thresholds for promoting abnormal grain growth in magnetostrictive Fe-Ga alloy sheets

Grain growth in Fe-Ga alloy is investigated to study the influence of NbC particles on grain boundary pinning and the promotion of abnormal grain growth (AGG) during anneals. AGG developed in samples with 1.0 and 2.5 mol.% NbC, whereas no grain growth occurred for inclusion of 0.5 and 4.0% NbC after primary recrystallization. Pinning force thresholds for AGG were determined empirically from fitting experimental results of grain configurations to a model based on equating driving force for grain growth to Smith-Zener drag force.