Correlation between grain misorientation, texture and impact toughness across a flash butt weld of HSLA steel

摘要

Flash butt welds show variation in impact toughness from the fusion line (FL) to the parent material (PM). A direct correlation of the variation in toughness, (1 1 0)[0 0 1] Goss texture and grain boundary misorientation fractions were observed. PM texture transformed to Goss, rotated Goss and rotated cube components in the thermo-mechanically affected zone (TMAZ) due to the shear deformation experienced during the upsetting stage. Whereas in the heat affected zone (HAZ) adjacent to TMAZ only microstructural changes were observed. Formation of (1 1 0)[0 0 1] texture component, higher fraction of Low Angle Grain Boundaries (LABs) as a result of deformation close to FL resulted in deterioration of toughness. (C) 2018 Elsevier B.V. All rights reserved.