Targeted adjustment of residual stresses in hot-formed components by means of process design based on finite element simulation

authored by: B. ‐.A. Behrens, K. Brunotte, H. Wester, C. Kock
Abstract: The aim of this work is to generate an advantageous compressive residual stress distribution in the surface area of hot-formed components by intelligent process control with tailored cooling. Adapted cooling is achieved by partial or temporal instationary exposure of the specimens to a water–air spray. In this way, macroscopic effects such as local plastification caused by inhomogeneous strains due to thermal and transformation-induced loads can be controlled in order to finally customise the surface-near residual stress distribution. Applications for hot-formed components often require special microstructural properties, which guarantee a certain hardness or ductility. For this reason, the scientific challenge of this work is to generate different residual stress distributions on components surfaces, while the geometric as well as microstructural properties of AISI 52100 alloy stay the same. The changes in the residual stresses should therefore not result from the mentioned changed component properties, but solely from the targeted process control. Within the scope of preliminary experimental studies, tensile residual stresses in a martensitic microstructure were determined on reference components, which had undergone a simple cooling in water (from the forming heat), or low compressive stresses in pearlitic microstructures were determined after simple cooling in atmospheric air. Numerical studies are used to design two tailored cooling strategies capable of generating compressive stresses in the same components. The developed processes with tailored cooling are experimentally realised, and their properties are compared to those of components manufactured involving simple cooling. Based on the numerical and experimental analyses, this work demonstrates that it is possible to influence and even invert the sign of the residual stresses within a component by controlling the macroscopic effects mentioned above.
Organisation(s): Institute of Metal Forming and Metal Forming Machines
Type: Article
Journal: Archive of applied mechanics
Volume: 91
Pages: 3579-3602
No. of pages: 24
ISSN: 0939-1533
Publication date: 08.2021
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Mechanical Engineering
Electronic version(s): https://doi.org/10.1007/s00419-021-01928-y (Access: Open)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{b7dadccd4fb5415cb6d1cbfe1ed74aed,
title = "Targeted adjustment of residual stresses in hot-formed components by means of process design based on finite element simulation",
abstract = "The aim of this work is to generate an advantageous compressive residual stress distribution in the surface area of hot-formed components by intelligent process control with tailored cooling. Adapted cooling is achieved by partial or temporal instationary exposure of the specimens to a water–air spray. In this way, macroscopic effects such as local plastification caused by inhomogeneous strains due to thermal and transformation-induced loads can be controlled in order to finally customise the surface-near residual stress distribution. Applications for hot-formed components often require special microstructural properties, which guarantee a certain hardness or ductility. For this reason, the scientific challenge of this work is to generate different residual stress distributions on components surfaces, while the geometric as well as microstructural properties of AISI 52100 alloy stay the same. The changes in the residual stresses should therefore not result from the mentioned changed component properties, but solely from the targeted process control. Within the scope of preliminary experimental studies, tensile residual stresses in a martensitic microstructure were determined on reference components, which had undergone a simple cooling in water (from the forming heat), or low compressive stresses in pearlitic microstructures were determined after simple cooling in atmospheric air. Numerical studies are used to design two tailored cooling strategies capable of generating compressive stresses in the same components. The developed processes with tailored cooling are experimentally realised, and their properties are compared to those of components manufactured involving simple cooling. Based on the numerical and experimental analyses, this work demonstrates that it is possible to influence and even invert the sign of the residual stresses within a component by controlling the macroscopic effects mentioned above.",
keywords = "FE-based process design, Hot forming, Residual stresses, Tailored cooling",
author = "Behrens, {B. ‐.A.} and K. Brunotte and H. Wester and C. Kock",
note = "Funding Information: Open Access funding enabled and organized by Projekt DEAL.. This study was funded by the German Research Foundation (DFG, Deutsche Forschungsgemeinschaft)-374871564 (BE 1691/223-2) within the priority program SPP 2013. ",
year = "2021",
month = aug,
doi = "10.1007/s00419-021-01928-y",
language = "English",
volume = "91",
pages = "3579--3602",
journal = "Archive of applied mechanics",
issn = "0939-1533",
publisher = "Springer Verlag",
number = "8",
}