Modeling Bainitic Transformations during Press Hardening

Materials, vol. 14, pp. 654

Abstract

We revisit recent findings on experimental and modeling investigations of bainitic transformations under the influence of external stresses and pre-strain during the press hardening process. Experimentally, the transformation kinetics in 22MnB5 under various tensile stresses are studied both on the macroscopic and microstructural level. In the bainitic microstructure, the variant selection effect is analyzed with an optimized prior-austenite grain reconstruction technique. The resulting observations are expressed phenomenologically using a autocatalytic transformation model, which serves for further scale bridging descriptions of the underlying thermo-chemo-mechanical coupling processes during the bainitic transformation. Using analyses of orientation relationships, thermodynamically consistent and nondiagonal phase field models are developed, which are supported by ab initio generated mechanical parameters. Applications are related to the microstructure evolution on the sheaf, subunit, precipitate and grain boundary level.

Authors 6

1. Mingxuan Lin corresponding Aachen Instituts für Eisenhüttenkunde

   RWTH Aachen University

   Affiliation as printed

   Instituts für Eisenhüttenkunde, RWTH Aachen University, 52072 Aachen, Germany

2. Carina Zimmermann

   Leibniz-Institut für Werkstofforientierte Technologien - IWT

   Affiliation as printed

   Leibniz-Institut für Werkstofforientierte Technologien—IWT, 28359 Bremen, Germany

3. Kai Wang

   Forschungszentrum Jülich

   Affiliation as printed

   Institut für Energie- und Klimaforschung IEK-2, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany

4. Martin Hunkel

   Leibniz-Institut für Werkstofforientierte Technologien - IWT

   Affiliation as printed

   Leibniz-Institut für Werkstofforientierte Technologien—IWT, 28359 Bremen, Germany

5. Ulrich Prahl Aachen Instituts für Eisenhüttenkunde

   TU Bergakademie Freiberg · RWTH Aachen University

   Affiliation as printed

   Institut für Metallformung, Technische Universität Bergakademie Freiberg, 09599 Freiberg, Germany

   Instituts für Eisenhüttenkunde, RWTH Aachen University, 52072 Aachen, Germany

6. Robert Spatschek

   Forschungszentrum Jülich · Jülich Aachen Research Alliance

   Affiliation as printed

   Institut für Energie- und Klimaforschung IEK-2, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany

   JARA-ENERGY, 52425 Jülich, Germany