Characterization of Microstructure and Microtexture in a Cold-Rolled and Intercritically Annealed Dual-Phase Steel

Microstructure and microtexture of a dual-phase (DP) steel was investigated using the electron backscattered diffraction (EBSD) technique. A DP600 steel was produced by 60% cold-rolling a low carbon steel with an initial ferrite pearlite microstructure followed by intercritical annealing at 720°C for 1 h. Kernel average misorientation map of the DP600 steel showed that the density of geometrically necessary dislocations as well as the local misorientation is higher in the vicinity of ferrite–martensite interfaces compared to the middle of the ferrite grains. Microtexture analysis of the cold-rolled steel by EBSD revealed that a strong α fiber and weaker γ fiber texture forms after cold-rolling. After intercritical annealing, the intensity of the α fiber texture is significantly reduced, whereas that of the more desirable γ fiber texture is slightly increased. The maximum texture intensity in the DP600 steel was observed for (112)[110] component in the α fiber, and (111)[123] and (111)[112] components in the γ fiber.