New insights on recovery and early recrystallization of ferrite-pearlite banded cold rolled high strength steels by high speed nano-indentation mapping

This work unravels structure-property correlations at the micrometer length scale during recovery and early recrystallization of a cold rolled high strength steel comprised of ferrite and pearlite. High resolution nano-indention mapping is used to measure the hardness of ferrite, pearlite and the transition zone between them, which correlates well with the local microstructure obtained from scanning and transmission electron microscopy. A clustering algorithm is used to determine the properties of the constituent microstructural features. The variation in the hardness of the phases with annealing temperature agrees well with the dislocation activity observed using Transmission Electron Microscopy (TEM) and a simple mechanism to reconcile the observations is presented. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Automated summary

This study investigates the structure-property correlations at the micrometer length scale during recovery and early recrystallization of a cold rolled high strength steel composed of ferrite and pearlite. High resolution nano-indention mapping technique and electron microscopy were used to study the local microstructure and hardness variations with annealing temperature. A clustering algorithm was employed to determine the properties of the constituent microstructural features.