Adjusting Mechanical Properties of Forging Dies Produced by Ausforming

authored by: Bernd Arno Behrens, Kai Brunotte, Tom Petersen, Corvin Ostermeyer, Michael Till
Abstract: Due to high thermo-mechanical loads, tools used in hot forming operations need a high resistance to different damage phenomena, such as deformation, cracking and abrasion. They are exposed to cyclic thermo-mechanical stress conditions, which leads to tool failure and subsequent tool replacement during cost-intensive production interruptions. To increase wear resistance, forging tools can be produced in the metastable austenite area. Forming of steel below the recrystallisation temperature, also known as “ausforming”, offers the possibility to increase strength without affecting ductile properties. This is due to grain refinement during forming. In this study, the thermo-mechanical treatment ausforming will be used to form the final contour of forging dies. For this purpose, an analogy study was performed where a cup-preform is ausformed, which represents the inner contour of a highly mechanically loaded forging die. It is investigated to what extent a fine-grained microstructure generated in the last forming stage can be achieved and how it influences the tool's performance. The hot-working tool steel X37CrMoV5-1 (AISI H11) was used as workpiece material. To achieve optimal properties, process routes with tempering temperatures from 300 °C to 500 °C and global true plastic strains of φ = 0.25 and φ = 0.45 were examined. The results were evaluated by pulsation tests, metallographic analysis and hardness measurements of the formed parts. Optimal ausforming parameters were derived to produce a high performance forging die.
Organisation(s): Institute of Metal Forming and Metal Forming Machines
Type: Conference contribution
Publication date: 02.04.2021
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Materials Science(all)
Electronic version(s): https://doi.org/10.25518/esaform21.2697 (Access: Open)
: Details in the research portal "Research@Leibniz University"

BibTeX

@inproceedings{913e1c12744a48c592b47562a0931e19,
title = "Adjusting Mechanical Properties of Forging Dies Produced by Ausforming",
abstract = "Due to high thermo-mechanical loads, tools used in hot forming operations need a high resistance to different damage phenomena, such as deformation, cracking and abrasion. They are exposed to cyclic thermo-mechanical stress conditions, which leads to tool failure and subsequent tool replacement during cost-intensive production interruptions. To increase wear resistance, forging tools can be produced in the metastable austenite area. Forming of steel below the recrystallisation temperature, also known as “ausforming”, offers the possibility to increase strength without affecting ductile properties. This is due to grain refinement during forming. In this study, the thermo-mechanical treatment ausforming will be used to form the final contour of forging dies. For this purpose, an analogy study was performed where a cup-preform is ausformed, which represents the inner contour of a highly mechanically loaded forging die. It is investigated to what extent a fine-grained microstructure generated in the last forming stage can be achieved and how it influences the tool's performance. The hot-working tool steel X37CrMoV5-1 (AISI H11) was used as workpiece material. To achieve optimal properties, process routes with tempering temperatures from 300 °C to 500 °C and global true plastic strains of φ = 0.25 and φ = 0.45 were examined. The results were evaluated by pulsation tests, metallographic analysis and hardness measurements of the formed parts. Optimal ausforming parameters were derived to produce a high performance forging die.",
keywords = "Ausforming, Bulk metal forming, Metastable austenite, Pulsation test, Wear",
author = "Behrens, {Bernd Arno} and Kai Brunotte and Tom Petersen and Corvin Ostermeyer and Michael Till",
note = "Funding Information: The authors would like to thank the German Research Foundation DFG for the financial support of the project (nr. 318628894). ; 24th International ESAFORM Conference on Material Forming, ESAFORM 2021 ; Conference date: 14-04-2021 Through 16-04-2021",
year = "2021",
month = apr,
day = "2",
doi = "10.25518/esaform21.2697",
language = "English",
isbn = "978-2-87019-302-0",
booktitle = "ESAFORM 2021 - 24th International Conference on Material Forming",
publisher = "ULi{\`e}ge Library",
}