Simulation of bar rolling in gleeble

Simulation of bar rolling was attempted in Gleeble 3500. Entire bar rolling was simulated, i.e., roughening rolling at higher temperature and finishing rolling at lower temperature. Torsion module was used to simulate the large amount of deformation employed in bar rolling. The equivalent strains and strain rates appropriate for torsion deformation in Gleeble were calculated as per standard industrial schedule, from roughening rolling to finishing rolling. The cooling schedules between the roughening rolling and finishing rolling and afterwards was also maintained as per industrial conditions. An induction hardenable grade of steel was selected to evaluate the possibility of simulating bar rolling in Gleeble. The torsion-torque response of the Gleeble simulation indicates whether dynamic restoration processes are active during the deformation steps. The microstructure and hardness of the Gleeble simulated samples were compared with the industrially hot-rolled bar

RVE Simulation of Hole-Expansion Formability of Dual-phase Steels

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Hole-expansion formability of dual-phase steels using representative volume element approach with boundary-smoothing technique

A qualitative analysis was carried out on the formability of dual-phase (DP) steels by introducing a realistic microstructure-based finite element approach. The present microstructure-based model was constructed using a mesh generation process with a boundary-smoothing algorithm after proper image processing. The developed model was applied to hole-expansion formability tests for DP steel sheets having different volume fractions and morphological features. On the basis of the microstructural inhomogeneity observed in the scanning electron micrographs of the DP steel sheets, it was inferred that the localized plastic deformation in the ferritic phase might be closely related to the macroscopic formability of DP steel. The experimentally observed difference between the hole-expansion formability of two different microstructures was reasonably explained by using the present finite element model. (C) 2010 Elsevier B.V. All rights reserved.X114444sciescopu