Orientation dependence of local lattice rotations at precipitates: Example of κ-Fe3AlC carbides in a Fe3Al-based alloy

Local lattice rotations and in-grain orientation gradients at kappa precipitates in matrix grains with orientations near the 45 degrees rotated cube {0 0 1}< 1 1 0 > (RC) and the gamma-fiber components {1 1 1}< 1 1 2 > were investigated in a Fe3Al alloy warm-rolled to reductions of between 10% and 60%. Near-RC grains showed larger local lattice rotations at precipitates than gamma-fiber grains. In RC-oriented grains the local lattice rotations about the transverse direction (TD) were dominant at low reductions, but rotations about the rolling direction (RD) also occurred at higher strains. In the gamma-fiber grains the axes of the in-grain lattice rotations were scattered between TD and RD. The rotations around the particles and their orientation dependence were analyzed using 3-D crystal plasticity finite-element simulations of a spherical inclusion in a plane strain deformed matrix of different orientations, namely RC, {1 1 1}< 1 1 2 > and {1 1 1}< 0 1 1 >. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.