Bimodal Grain Size Distribution Enhances Strength and Ductility Simultaneously in a Low-Carbon Low-Alloy Steel

Author(s)
Peter J. Szabo, David P. Field, Bertalan Joni, Jelena Horky, Tamas Ungar
Abstract

Low-carbon low-alloy steel specimens were quenched, then cold rolled, and finally annealed. Electron backscatter diffraction (EBSD) micrographs revealed a bimodal grain structure where ultra-fine grain structures with low-angle grain boundaries are alternating with regions of larger grains. The average total dislocation density was measured by X-ray line profile analysis, whereas the geometrically necessary dislocation density was obtained from the analysis of EBSD data. Using the combination of the Hall-Petch and Taylor equations, a good correlation was found between the total dislocation density and the measured flow stress in the different states of the alloy. The difference in evolutions of the total and the geometrically necessary component of the dislocation densities is discussed in terms of the successive processes of quenching, rolling, and annealing of the alloy.

Organisation(s)
Physics of Nanostructured Materials
External organisation(s)
Budapest University of Technology and Economics, Washington State University, Eötvös Loránd University Budapest, City University of Hong Kong (CityU)
Journal
Metallurgical and Materials Transactions A - Physical Metallurgy and Materials Science
Volume
46
Pages
1948-1957
No. of pages
10
ISSN
1073-5623
DOI
https://doi.org/10.1007/s11661-015-2783-x
Publication date
05-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103018 Materials physics
Keywords
ASJC Scopus subject areas
Condensed Matter Physics, Mechanics of Materials, Metals and Alloys
Portal url
https://ucris.univie.ac.at/portal/en/publications/bimodal-grain-size-distribution-enhances-strength-and-ductility-simultaneously-in-a-lowcarbon-lowalloy-steel(b7de0b50-ce20-448c-8a2a-e9bb24260b00).html