Numerical and experimental investigations of the anisotropic transformation strains during martensitic transformation in a low alloy Cr-Mo steel 42CrMo4

authored by: Bernd Arno Behrens, Anas Bouguecha, Christian Bonk, Alexander Chugreev
Abstract: Hot forming as a coupled thermo-mechanical process comprises of numerous material phenomena with a corresponding impact on the material behavior during and after the forming process. Within the subsequent heat treatment, possible rapid cooling of the hot formed parts leads to the diffusionless decomposition of austenite into martensite. In this context, in addition to the elastic, plastic and linear thermal strain components, complex isotropic as well as anisotropic transformation strains can occur. Irreversible anisotropic transformation strains account for the plastic deformation at the phase boundary between the emerging and the parent phase and are related to the transformation induced plasticity (TRIP or TP) phenomena. Moreover, TRIP strains can be reduced or amplified by varying the current stress state. These phenomena significantly contribute to the final residual stress state and may be responsible for the cost-intensive component defects arising due to thermal shrinkage. This study aims at developing an FE-based material model in order to describe and quantitatively visualize stress dependence of the transformation induced anisotropic strains for a typical forging steel 42CrMo4. The developed material model as well as the aspects of its implementation in a commercial FE-system (Simufact.forming) is presented. Consequently, the discussed material model is tested by comparison of experimental and numerical results with respect to resulting dilatation under various stress states.
Organisation(s): Institute of Metal Forming and Metal Forming Machines
Type: Conference article
Journal: Procedia Engineering
Volume: 207
Pages: 1815-1820
No. of pages: 6
ISSN: 1877-7058
Publication date: 15.11.2017
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: General Engineering
Electronic version(s): https://doi.org/10.1016/j.proeng.2017.10.944 (Access: Open)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{9cdd01383d51430fa06c794babd99f00,
title = "Numerical and experimental investigations of the anisotropic transformation strains during martensitic transformation in a low alloy Cr-Mo steel 42CrMo4",
abstract = "Hot forming as a coupled thermo-mechanical process comprises of numerous material phenomena with a corresponding impact on the material behavior during and after the forming process. Within the subsequent heat treatment, possible rapid cooling of the hot formed parts leads to the diffusionless decomposition of austenite into martensite. In this context, in addition to the elastic, plastic and linear thermal strain components, complex isotropic as well as anisotropic transformation strains can occur. Irreversible anisotropic transformation strains account for the plastic deformation at the phase boundary between the emerging and the parent phase and are related to the transformation induced plasticity (TRIP or TP) phenomena. Moreover, TRIP strains can be reduced or amplified by varying the current stress state. These phenomena significantly contribute to the final residual stress state and may be responsible for the cost-intensive component defects arising due to thermal shrinkage. This study aims at developing an FE-based material model in order to describe and quantitatively visualize stress dependence of the transformation induced anisotropic strains for a typical forging steel 42CrMo4. The developed material model as well as the aspects of its implementation in a commercial FE-system (Simufact.forming) is presented. Consequently, the discussed material model is tested by comparison of experimental and numerical results with respect to resulting dilatation under various stress states.",
keywords = "42CrMo4, finite element analysis, multiscale material modelling, transformation induced plasticity",
author = "Behrens, {Bernd Arno} and Anas Bouguecha and Christian Bonk and Alexander Chugreev",
note = "Funding information: The authors wish to express sincere thanks to the German Research Foundation (DFG) for financial support of the research project BE1691/142-1 Siulatiom“n of te h undesired distortions in hot forged and subsequently heat trpeatedeocontsconnidme seriingacmt fnteadsutressytate sstnotrhrfsatiopnmicitlast”.y; International Conference on the Technology of Plasticity, ICTP 2017 ; Conference date: 17-09-2017 Through 22-09-2017",
year = "2017",
month = nov,
day = "15",
doi = "10.1016/j.proeng.2017.10.944",
language = "English",
volume = "207",
pages = "1815--1820",
journal = "Procedia Engineering",
issn = "1877-7058",
publisher = "Elsevier BV",
}