Estimating the strain-rate-dependent parameters of the Johnson-Cook material model using optimisation algorithms combined with a response surface

Škrlec, Andrej (author), Klemenc, Jernej (author)

Under conditions where a product is subjected to extreme mechanical loading over a very short time period, the strain rate has considerable influence on the behaviour of the product’s material. To simulate the behaviour of the material accurately under these loading conditions, the appropriate strain-rate parameters for the selected material model should be used. The aim of this paper is to present a quick method for easily determining the appropriate strain-rate-dependent parameter values of the selected material model. The optimisation procedure described in the article combines the design-of-experiment (DoE) technique, finite-element simulations, modelling a response surface and an evolutionary algorithm. First, a non-standard dynamic experiment was designed to study the behaviour of thin, flat, metal sheets during an impact. The experimental data from this dynamic and the conventional tensile experiments for mild steel were the basis for the determination of the Johnson-Cook material model parameters. The paper provides a comparison of two optimisation processes with different DoE techniques and with three different optimisation algorithms (one traditional and two metaheuristic). The performances of the presented method are compared, and the engineering applicability of the results is discussed. The identified parameter values, which were estimated with the presented procedure, are very similar to those from the literature. The paper shows how the application of a properly designed plan of simulations can significantly reduce the simulation time, with only a minor influence on the estimated parameters. Furthermore, it can be concluded that in some cases the traditional optimisation method is as good as the two metaheuristic methods. Finally, it was proven that experiments with different strain rates must be carried out when estimating the corresponding material parameters.

• Language: English
• Keywords: strain rate, finite-element method, design of experiment, Taguchi orthogonal array, response surface, evolutionary algorithm, Johnson-Cook material mode
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FS - Faculty of Mechanical Engineering
• Publication status: Published
• Publication version: Version of Record
• Year: 2020
• Number of pages: 18 str.
• Numbering: Vol. 8, iss. 7, art. 1105
• PID: 20.500.12556/RUL-117669
• UDC: 519.61(045)
• ISSN on article: 2227-7390
• DOI: 10.3390/math8071105
• COBISS.SI-ID: 23026947
• Publication date in RUL: 20.07.2020

Record is a part of a journal

• Title: Mathematics
• Shortened title: Mathematics
• Publisher: MDPI AG
• ISSN: 2227-7390
• COBISS.SI-ID: 523267865

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.
• Licensing start date: 05.07.2020

Secondary language

• Language: Slovenian
• Keywords: hitrost specifične deformacije, metoda končnih elementov, metoda načrtovanja preizkusov, Taguchijeva matrika, odzivna površina, evolucijski algoritem, Johnson-Cook materialni model

Projects

• Funder: ARRS - Slovenian Research Agency
• Project number: P2-0182
• Name: Razvojna vrednotenja