Microstructural Changes by Annealing in Ultrafine-Grained Electrodeposited Pure Iron

In situ neutron diffraction during annealing was performed for ultrafine-grained as-deposited and cold-rolled pure iron. Changes in the integrated intensity and full-width at half-maximum in the diffraction profiles during annealing were measured. EBSD measurements were performed before and after annealing to obtain microstructural change. Abnormal grain growth was clearly found at 673 K (400 degrees C) upon annealing; this observation corresponds to the hydrogen desorption behavior of the as-deposited specimen. The texture changes from {111} < hkl > to {211} < hkl > between 673 K and 873 K (400 degrees C and 600 degrees C) upon continuous heating. Such a texture change is postulated to decrease the Lankford value from 7.6 to 2.2. The 40 pct cold-rolled specimen exhibited a complicated textural evolution upon annealing, which was caused by the intrusion of recrystallization at deformation bands. (C) The Minerals, Metals & Materials Society and ASM International 2013