Behaviors of Normal Grain Growth in Polycrystalline Fe–3%Si Alloys

Abstract

The grain growth processes of model alloys Fe–3%Si–MnS and Fe–3%Si were investigated. The MnS particles did not completely inhibit normal grain growth but drastically reduced growth velocity. Activation enthalpy (57.72 kJ mol−1) and pre‐exponential factor (7.82 × 10−9 m2 s−1) for boundary migration obtained by statistical regressive calculations were significantly lower than those obtained by bicrystal investigations. The observations indicated that atoms should be pre‐activated before they jump over moving boundaries. Activation enthalpy and pre‐exponential factor decreased with increased pre‐activation energy. The predominant migrations of strongly curved boundaries and triple junctions during grain growth in polycrystals increased the pre‐activation energy, which differed from the simplified behaviors of boundary migration in bicrystals.