Full metadata record
DC Field | Value | Language |
---|---|---|
dc.contributor.author | 한정호 | - |
dc.date.accessioned | 2019-09-17T05:55:41Z | - |
dc.date.available | 2019-09-17T05:55:41Z | - |
dc.date.issued | 2019-03 | - |
dc.identifier.citation | ACTA MATERIALIA , v.166 ,Page. 512-530 | en_US |
dc.identifier.issn | 1359-6454 | - |
dc.identifier.issn | 1873-2453 | - |
dc.identifier.uri | https://www.sciencedirect.com/science/article/pii/S1359645419300060?via%3Dihub | - |
dc.identifier.uri | https://repository.hanyang.ac.kr/handle/20.500.11754/110463 | - |
dc.description.abstract | A medium-Mn steel (Fe-12Mn-3Al-0.05C wt%) was designed using Thermo-Calc (R) simulations to balance the fraction and stacking fault energy of reverted austenite. lntercritical annealing for 0.5, 8 and 48 h was carried out at 585 degrees C to investigate the microstructural evolution. X-ray diffraction (XRD), electron backscatter diffraction (EBSD), 3-dimensional EBSD, energy-dispersive spectroscopy via scanning transmission electron microscopy (STEM-EDS) and atom probe tomography (APT) enable characterization of phase fraction, grain area, grain morphology and alloy partitioning. An increase in annealing time from 0.5 h to 48 h increases the amount of ultrafine-grained (UFG) reverted austenite from 3 to 40 vol %. EBSD and TEM reveal multiple morphologies of UFG austenite (equiaxed, rod-like and plate-like). In addition, most of the remaining microstructure consists of recovered alpha'-martensite that resembles the cold-rolled state, as well as a relatively small fraction of UFG ferrite (i.e., only a small amount of martensite recrystallization occurs). Multi-scale characterization results show that the location within the cold-rolled microstructure has a strong influence on boundary mobility and grain morphology during austenite reversion. Results from APT reveal Mn-decoration of dislocation networks and low-angle lath boundaries in the recovered alpha'-martensite, but an absence of Mn-decoration of defects in the vicinity of austenite grains, thereby promoting recovery. STEM-EDS and APT reveal Mn depletion zones in the ferrite/recovered alpha'-martensite near austenite boundaries, whereas gradients of C and Mn co-partitioning are visible within some of the austenite grains after annealing for 0.5 h. Relatively flat C enriched austenite boundaries are present even after 8 h of annealing and indicate certain boundaries possess low mobility. At later stages the growth of austenite followed the local equilibrium (LE) model such that the driving force between two equilibrium phases moves the mobile interface, as confirmed by DICTRA simulations (a Thermo-Calc (R) diffusion module). The sequence of austenite reversion is: (i) formation of Mn- and C-enriched face-centered-cubic nuclei from decorated dislocations and/or particles; (ii) co-partitioning of Mn and C and (iii) growth of austenite controlled by the LE mode. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved. | en_US |
dc.description.sponsorship | This work was funded by the United States National Science Foundation (NSF) under grants NSF DMR 1309258 and NSF EPS 1004083. The Max-Planck-Institute fur Eisenforschung in Dusseldorf, Germany and Thermo Scientific in Hillsboro, OR also provided resources necessary to complete this research. The authors are grateful to U. Tezins and A. Sturm for their technical support of the atom probe tomography and focused ion beam facilities at the MaxPlanck-Institut fur Eisenforschung. A.K.S. is grateful to the Brazilian National Research Council (Conselho Nacional de Pesquisas, CNPQ) for the Ph.D. scholarship through the "Science without Borders" Project (203077/2014-8). | en_US |
dc.language.iso | en | en_US |
dc.publisher | PERGAMON-ELSEVIER SCIENCE LTD | en_US |
dc.subject | Austenite reversion | en_US |
dc.subject | Martensite recovery | en_US |
dc.subject | Medium-Mn steel | en_US |
dc.subject | FIB tomography | en_US |
dc.subject | 3D EBSD | en_US |
dc.subject | STEM EDS | en_US |
dc.subject | Atom probe tomography | en_US |
dc.subject | Thermo-Calc (R) | en_US |
dc.subject | DICTRA | en_US |
dc.title | Multi-scale characterization of austenite reversion and martensite recovery in a cold-rolled medium-Mn steel | en_US |
dc.type | Article | en_US |
dc.identifier.doi | 10.1016/j.actamat.2019.01.003 | - |
dc.relation.journal | ACTA MATERIALIA | - |
dc.contributor.googleauthor | Benzing, J. T. | - |
dc.contributor.googleauthor | da Silva, A. Kwiatkowski | - |
dc.contributor.googleauthor | Morsdorf, L. | - |
dc.contributor.googleauthor | Bentley, J. | - |
dc.contributor.googleauthor | Ponge, D. | - |
dc.contributor.googleauthor | Dutta, A. | - |
dc.contributor.googleauthor | Han, Jeongho | - |
dc.contributor.googleauthor | McBride, J. R. | - |
dc.contributor.googleauthor | Van Leer, B. | - |
dc.contributor.googleauthor | Gault, B. | - |
dc.relation.code | 2019002680 | - |
dc.sector.campus | S | - |
dc.sector.daehak | COLLEGE OF ENGINEERING[S] | - |
dc.sector.department | DIVISION OF MATERIALS SCIENCE AND ENGINEERING | - |
dc.identifier.pid | jeonghohan | - |
dc.identifier.orcid | https://orcid.org/0000-0002-0126-9314 | - |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.