GRAIN INTERACTION AND RELATED ELASTIC FIELDS AT TRIPLE JUNCTION IN LOW DEFORMED IF STEEL: MICROMECHANICAL MODEL AND RECONSTRUCTION FROM EBSD ORIENTATION DATA

摘要

Incompatible plastic strains of grains, forming a triple junction in a low deformed IF steel, have been reconstructed from their interfacial disorientations with a simple micromechanical model that suggests the minimum level of internal stresses. Then, based on these strains, respective defects induced on the grain boundaries are quantified and related long-range fields of elastic rotation and stress are calculated. The calculated rotation field, accommodating the strain induced part of interfacial disorientations, proves to fit satisfactorily EBSD orientation data and evidences for a disclination of about 3° on the junction line and planar stress sources on the involved boundaries. The corresponding stress field locates probable areas of plastic accommodation, which are also in good correspondence with appropriate features of the EBSD data.