ICAMS Members

Dr.-Ing. Napat Vajragupta
Research Group LeaderGroup: Micromechanics of Large Deformations
Department of Micromechanical and Macroscopic ModellingICAMS
Ruhr-Universität Bochum
IC 02-569
Universitätsstr. 150
44801 Bochum
Tel. +49 234 32 22417
Email: Napat Vajragupta
ORCID ID: 0000-0001-6085-7493
Micromechanical modeling
damage mechanics
representative volume element
Research Interests:
Micromechanical modeling
damage mechanics
representative volume element
- M. Ramaswamy Guru Prasad, S. Gao, N. Vajragupta, A. Hartmaier.
Influence of trapped gas on pore healing under hot isostatic pressing in nickel-base superalloys, Crystals, MDPI, Basel/Switzerland, 10, 1147, (2020)
- M. Ramaswamy Guru Prasad, A. Biswas, W. Amin, S. Gao et al.
Influence of pore characteristics on anisotropic mechanical behavior of L‐PBF manufactured metal by micromechanical modeling, Advanced Engineering Materials, 2000641, (2020)
- A. Biswas, M. Ramaswamy Guru Prasad, N. Vajragupta, A. Kostka et al.
Effect of grain statistics on micromechanical modeling: the example of additively manufactured materials examined by electron backscatter diffraction, Advanced Engineering Materials, Wiley Online Library, Germany, 22, 1901416, (2020)
- N. Vajragupta, S. Maassen, T. Clausmeyer, D. Brands et al.
Micromechanical modeling of DP600 steel: from microstructure to the sheet metal forming process, Procedia Manufacturing, 47, 1540-1547, (2020)
- M. Shahmardani Firouzjah, N. Vajragupta, A. Hartmaier.
Robust optimization scheme for inverse method for crystal plasticity model parametrization, Materials, Multidisciplinary Digital Publishing Institute, Basel, 13, 735, (2020)
- A. Biswas, M. Ramaswamy Guru Prasad, N. Vajragupta, A. Hartmaier.
Kanapy: synthetic polycrystalline microstructure generator with geometry and texture, Zenodo Repository, Zenodo, (2020)
- A. Biswas, N. Vajragupta, R. Hielscher, A. Hartmaier.
Optimized reconstruction of the crystallographic orientation density function based on a reduced set of orientations, Journal of Applied Crystallography, International Union of Crystallography, 53, 178-187, (2020)
- M. Ramaswamy Guru Prasad, N. Vajragupta, A. Hartmaier.
Kanapy: a Python package for generating complex synthetic polycrystalline microstructures, Journal of Open Source Software, 4, 1732, (2019)
- J. K. Engels, N. Vajragupta, A. Hartmaier.
Parameterization of a non-local crystal plasticity model for tempered lath martensite using nanoindentation and inverse method, Frontiers in Materials, 6, 247, (2019)
- W. Amin, M. A. Ali, N. Vajragupta, A. Hartmaier.
Studying grain boundary strengthening by dislocation-based strain gradient crystal plasticity coupled with a multi-phase-field model, Materials, MDPI, Basel, Switzerland, 12, 2977, (2019)
- D. Reimann, K. C. Nidadavolu, H. u. Hassan, N. Vajragupta et al.
Modeling macroscopic material behavior with machine learning algorithms trained by micromechanical simulations, Frontiers in Materials, 6, 181, (2019)
- A. Biswas, M. R. G. Prasad, N. Vajragupta, H. u. Hassan et al.
Influence of microstructural features on the strain hardening behavior of additively manufactured metallic components, Advanced Engineering Materials, Wiley Online Library, Germany, 21, 1900275, (2019)
- J. K. Engels, S. Gao, W. Amin, A. Biswas et al.
Indentation size effects in spherical nanoindentation analyzed by experiment and non-local crystal plasticity, Materialia, 3, 21-30, (2018)
- N. Vajragupta, H. u. Hassan, A. Hartmaier.
Towards prediction of springback in deep drawing using a micromechanical modeling scheme, Procedia Engineering, 207, 60-65, (2017)
- N. Vajragupta, S. Ahmed, M. Boeff, A. Ma et al.
Micromechanical modeling approach to derive the yield surface for BCC and FCC steels using statistically informed microstructure models and nonlocal crystal plasticity, Physical Mesomechanics, 20, 100-108, (2017)
- B. Wu, N. Vajragupta, J. Lian, U. Hangen et al.
Prediction of plasticity and damage initiation behaviour of C45E + N steel by micromechanical modelling, Materials & Design, 121, 154-166, (2017)
- Y. Di, J. Lian, B. Wu, N. Vajragupta et al.
The second blind Sandia Fracture Challenge: Improved MBW model predictions for different strain rates, International Journal of Fracture, 198, 149-165, (2016)
- B. L. Boyce, S. L. B. Kramer, T. R. Bosiljevac, E. Corona et al.
The second Sandia Fracture Challenge: Predictions of ductile failure under quasi-static and moderate-rate dynamic loading, International Journal of Fracture, 198, 5-100, (2016)
- J. Lian, N. Vajragupta, S. Münstermann, W. Bleck et al.
A method to quantitatively upscale the damage initiation of dual-phase steels under various stress states from microscale to macroscale, Computational Materials Science, 94, 245–257, (2014)
- N. Vajragupta, P. Wechsuwanmanee, J. Lian, M. Sharaf et al.
The modeling scheme to evaluate the influence of microstructure features on microcrack formation of DP-steel: the artificial microstructure model and its application to predict the strain hardening behavior, Computational Materials Science, 95, 198-213, (2014)
- M. Sharaf, P. Kucharczyk, N. Vajragupta, S. Münstermann et al.
Modeling the microstructure influence on fatigue life variability in structural steels, Computational Materials Science, 94, 258-272, (2014)
- S. Münstermann, N. Vajragupta, J. Lian.
Modeling the cold formability of dualphase steels on different length scales, Procedia Materials Science, 3, 1050–1055, (2014)
- S. Münstermann, J. Lian, N. Vajragupta.
Evaluation of the cold formability of multiphase steels by damage mechancis approaches, Materials Testing, 55, 628-635, (2013)
- N. Vajragupta, J. Lian, M. Sharaf, S. Münstermann et al.
The influence of grain size distribution on strain hardening behaviour for dual phase steels using statistically informed artificial microstructure model and crystal plasticity, Proceedings of the International Conference on Computational Plasticity, Fundamentals and Applications, COMPLAS XII, CIMNE, Barcelona, 1458-1470, (2013)
- J. Lian, N. Vajragupta, S. Münstermann.
Micromechanical modeling of damage and failure in dual phase steels, Key Engineering Materials, 554-557, 2369-2374, (2013)
- M. Sharaf, P. Kucharczyk, A. Ma, N. Vajragupta et al.
Assessment of fatigue microcrack initiation and growth capabilities in structural steels: an interdisciplinary experimental and numerical method, Proceedings of the 3rd International Conference of Engineering Against Failure, University of Patras & Hellenic Metallurgical Society, (2013)
- S. Münstermann, N. Vajragupta, B. Weisgerber, A. Kern.
A numerical study on the mechanical properties and the processing behaviour of composite high strength steels, Materials Testing, 55, 336-344, (2013)
- N. Vajragupta, J. Lian, S. Münstermann, W. Bleck.
The strategy to consider microstructure features on the formability of AHSS: characterization of grain boundary properties, MEFORM 2013: Simulation von Umformprozessen, TU Freiberg, (2013)
- M. Sharaf, J. Lian, N. Vajragupta, S. Münstermann et al.
Influence of microstructural features on the propagation of microstructurally short fatigue cracks in structural steels, Fatigue of Materials II, Springer Nature Switzerland AG, Cham (CH), 243-250, (2013)
- N. Vajragupta, V. Uthaisangsuk, B. Schmaling, S. Münstermann et al.
A micromechanical damage simulation of dual phase steels using XFEM, Computational Materials Science, 54, 271-279, (2012)
- J. Lian, N. Vajragupta, S. Münstermann, W. Bleck.
On application of a damage plasticity model to sheet metal forming of DP steel, Steel Research International Special Edition: 10th International Conference on Technology of Plasticity, Aachen, 901-906, (2011)
- J. Lian, N. Vajragupta, S. Münstermann.
Multiscale modeling of cold formability of DP steel using XFEM and the modified Mohr-Coulomb criterion, Proceeding, 26. Aachener Stahlkolloquium, Aachen, Germany, (2011)
- 21.04.2015FE simulation of nanoindentation tests with crystal plasticity finite element method and virtual experimentBo Wu, Napat Vajragupta, Junhe Lian, Yu Duan, Thanawat Lertsirarungsun, U Hangen, Sebastian Münstermann
Hysitron Nanobrücken Workshop and User Meeting 2015, Potsdam, Germany
- 04.10.2013The modelling scheme to evaluate the influence of microstructure features on microcrack formation of DP-steelNapat Vajragupta, Junhe Lian, Mohamed Sharaf, Sebastian Münstermann
23rd International Workshop on Computational Mechanics of Materials (IWCMM), Singapore
- 04.10.2013Numerical simulation of cyclic microcrack growth capability using a crystal plasticity based material model and its experimental validationMohamed Sharaf, Pawel Kucharczyk, Napat Vajragupta, Sebastian Münstermann, Alexander Hartmaier, Wolfgang Bleck
23rd International Workshop on Computational Mechanics of Materials (IWCMM), Singapore
- 05.09.2013The influence of grain size distribution on strain hardening behaviour for dual phase steels using statistically informed artificial microstructure model and crytsal plasticityNapat Vajragupta, Junhe Lian, Mohamed Sharaf, Sebastian Münstermann
COMPLAS XII, Barcelona, Spain
- 28.06.2013Assessment of fatigue microcrack initiation and growth capabilities in structural steels: an interdisciplinary experimental and numerical methodMohamed Sharaf, Pawel Kucharczyk, Anxin Ma, Napat Vajragupta, Sebastian Münstermann, Wolfgang Bleck
3rd International Conference of Engineering Against Failure (ICEAF III), Kos, Greece
- 20.03.2013The strategy to consider microstructure features on the formability of AHSS: characterization of grain boundary propertiesNapat Vajragupta, Junhe Lian, Sebastian Münstermann, Wolfgang Bleck
MEFORM 2013, Freiburg, Germany
- 22.09.2020Influence of porosity on plasticity and damage of SLM manufactured metal assessed by a micromechanical modeling schemeMahesh Ramaswamy Guru Prasad, Abhishek Biswas, Napat Vajragupta, Alexander Hartmaier
Material Science and Engineering 2020 (MSE-2020) Technical University Darmstadt Online conference
- 11.12.2019Mechanical property prediction of additively manufactured metals by micromechanical modellingNapat Vajragupta, Abhishek Biswas, Mahesh Ramaswamy Guru Prasad, Alexander Hartmaier
Materials Science and Technology of Additive Manufacturing (MSTAM) Bremen, Germany
- 13.11.2019Optimal reconstruction of crystallographic texture with a reduced set of orientationsAbhishek Biswas, Napat Vajragupta, Ralf Hielscher, Alexander Hartmaier
Arbeitskreise Mikrostrukturmechanik im FA Materials Modelling, Simulation and Data Siegen, Germany
- 13.11.2019Kanapy: A tool for generating complex synthetic polycrystalline microstructuresMahesh Ramaswamy Guru Prasad, Abhishek Biswas, Napat Vajragupta, Alexander Hartmaier
Arbeitskreise Mikrostrukturmechanik im FA Materials Modelling, Simulation and Data Siegen, Germany
- 21.05.2019Data-driven toolkit for property-based design of microstructuresNapat Vajragupta, Abhishek Biswas, Mahesh Ramaswamy Guru Prasad, Alexander Hartmaier
Ruhr-Universität Bochum ICAMS Advanced Discussions
- 19.02.2019Inverse analysis on tempered lath martensite: a materials science and methodological studyJenni Kristin Engels, Napat Vajragupta, Alexander Hartmaier
Nanobrücken 2019 Berlin, Germany
- 12.11.2018Micromechanical modeling of metals using crystal plasticity-phase field methodWaseem Amin, Napat Vajragupta, Alexander Hartmaier
The second Materials Chain International Conference, MCIC 2018 Session: Modelling and Simulation Ruhr-Universität Bochum 12-14 Nov. 2018
- 27.09.2018Parameterization of a nonlocal crystal plasticity model for lath martensite using nanoindentationJenni Kristin Engels, Napat Vajragupta, Alexander Hartmaier
Materials Science and Engineering (MSE) Darmstadt, Germany
- 27.09.2018Micromechanical modeling of DP600 steel: From microstructure to the sheet metal forming processNapat Vajragupta, Sascha Maassen, Dominik Brands, Till Clausmeyer, Jörg Schröder, Alexander Hartmaier
Materials Science and Engineering (MSE) Darmstadt, Germany
- 18.09.2018Texture evolution during uniaxial tensile test of additively manufactured 316L stainless steelAbhishek Biswas, Mahesh Ramaswamy Guru Prasad, Napat Vajragupta, Hamad ul Hassan, Florian Brenne, Alexander Hartmaier
6th International Symposium on Computational Mechanics of Polycrystals, Düsseldorf, Germany
- 17.09.2018Synthetic microstructure generation for additively manufactured superalloysMahesh Ramaswamy Guru Prasad, Napat Vajragupta, Alexander Hartmaier
6th International Symposium on Computational Mechanics of Polychrystals, Düsseldorf, Germany
- 18.07.2018A micromechanical modeling scheme to parameterize a loading-path- dependent hardening model for DC06 steelNapat Vajragupta, Srinivas Kamath, Till Clausmeyer, Alexander Hartmaier
18th International Conference on the Strength of Materials, Ohio, USA
- 26.06.2018Addressing the indentation size effect (ISE) in cono-spherical nanoindentation test using a nonlocal crystal plasticity modelNapat Vajragupta
10 Years ICAMS - International Symposium, Ruhr-Universität Bochum, Germany
- 26.06.2018Addressing the indentation size effect (ISE) in cono-spherical nanoindentation test using a nonlocal crystal plasticity modelNapat Vajragupta
10 Years ICAMS - International Symposium, Ruhr-Universität Bochum, Germany
- 25.06.2018Prediction of large deformations in FCC Metals using crystal platicity phase-field methodWaseem Amin, Napat Vajragupta, Alexander Hartmaier
10 Years ICAMS - International Symposium, Ruhr-Universität Bochum, Germany
- 25.06.2018Micromechanical modeling of additively manufactured 316L stainless steelAbhishek Biswas, Mahesh Ramaswamy Guru Prasad, Napat Vajragupta, Hamad ul Hassan, Florian Brenne, Alexander Hartmaier
10 Years ICAMS - International Symposium, Ruhr-Universität Bochum, Germany
- 25.06.2018Characterization of tempered lath martensite using nanoindentation and inverse methodJenni Kristin Engels, Napat Vajragupta, Alexander Hartmaier
10 Years ICAMS - International Symposium, Ruhr-Universität Bochum, Germany
- 11.12.2017Adressing an indentation size effect (ISE) in the nanoindentation test using a nonlocal crystal plasticity modelJenni Kristin Engels, Napat Vajragupta, Alexander Hartmaier
RUB Materials Day, Ruhr-Universität Bochum, Germany
- 20.09.2017Parameterization of a nonlocal crystal plasticity model by nanoindentation and inverse modelingJenni Kristin Engels, Waseem Amin, Abhishek Biswas, Siwen Gao, Daysi Karina Gonzalez Dacasa, Soheil Rooein, Napat Vajragupta, Alexander Hartmaier
27th International Workshop on Computional Mechanics of Materials (IWCMM27), Leuven, Belgium
- 18.09.2017Towards prediction of springback in deep drawing using a micromechanical modelling schemeNapat Vajragupta, Hamad ul Hassan, Alexander Hartmaier
The 12th International Conference on Technology of Plasticity (ICTP2017), Cambridge, UK
- 06.09.2017Parameterization of a nonlocal crystal plasticity model for tempered martensite by nanoindentation and inverse modellingNapat Vajragupta, Nishant Pillai, Jenni Kristin Engels, Alexander Hartmaier
XIV International Conference on Computational Plasticity. Fundamental and Applications (COMPLAS 2017), Barcelona, Spain
- 09.05.2017Towards prediction of springback in deep drawing using a micromechanical modelling schemeNapat Vajragupta, Hamad ul Hassan, Alexander Hartmaier
ICAMS Advanced Discussions, Bochum, Germany
- 24.09.2014Structural steel endurance: towards the optimum microstructure fatigue resistanceMohamed Sharaf, Sebastian Münstermann, Napat Vajragupta, Pawel Kucharczyk, Alexander Hartmaier, Wolfgang Bleck
Materials Science and Engineering MSE 2014, Darmstadt, Germany
- 11.06.2014The fatigue limit of steel: a numerical solution to the short cracks problemMohamed Sharaf, Napat Vajragupta, Sebastian Münstermann, Pawel Kucharczyk, Alexander Hartmaier, Wolfgang Bleck
The 2nd International Symposium on Fatigue Design & Material Defects, Paris, France
- 27.03.2014Steel endurance: from microstructure to fatigue propertiesMohamed Sharaf, Pawel Kucharczyk, Napat Vajragupta, Sebastian Münstermann, Alexander Hartmaier, Wolfgang Bleck
29th Aachen Stahlkolloquium, Aachen, Germany
- 11.11.2013Fatigue modelling of steels: an application of the artificial microstructure modelMohamed Sharaf, Napat Vajragupta
ICAMS Advanced Discussions, Bochum, Germany
- 06.12.2012Schädigungsmechanische Bewertung der Kaltumformbarkeit von mehrphasigen StählenSebastian Münstermann, Junhe Lian, Napat Vajragupta
DGM-Tagung Werkstoffprüfung 2012, Bad Neuenahr, Germany
- 07.10.2012Crystal plasticity modelling on single crystal and polycrystal of a ferritic steel sheetJunhe Lian, Siwen Gao, Mohamed Sharaf, Napat Vajragupta, Benjamin Schmaling, Anxin Ma, Sebastian Münstermann, Alexander Hartmaier, Wolfgang Bleck
Materials Science & Technology 2012 Pittsburgh, USA
- 24.09.2012Generation of statistically-based RVE for dual-phase microstructure using multiplicative weighted Voronoi tessellation and the application to crystal plasticityNapat Vajragupta, Junhe Lian, Mohamed Sharaf, Benjamin Schmaling, Anxin Ma, Sebastian Münstermann, Alexander Hartmaier, Wolfgang Bleck
International workshop on computational mechanics of materials IWCMM XXII
- 28.09.2011On application of a damage plasticity model to sheet metal forming of DP SteelJunhe Lian, Napat Vajragupta, Sebastian Münstermann, Wolfgang Bleck
10th International Conference on Technology of Plasticity (ICTP 2011), Aachen, Germany
- 20.05.2011Multiscale modelling of cold formability of DP steel using XFEM and the modified Mohr-Coulomb criterionJunhe Lian, Napat Vajragupta, Sebastian Münstermann
ASK 2011 - 26. Aachener Stahl Kolloquium Werkstofftechnik EUROGRESS Aachen, Germany
- 23.03.2011Micromechanical damage modeling of multiphase steelsNapat Vajragupta, V. Uthaisangsuk, Sebastian Münstermann, Wolfgang Bleck
Sitzung des Arbeitskreises Mikrostrukturmechanik im Fachausschuss Computersimulation der Deutschen Gesellschaft für Materialkunde, Aachen, Germany
- 08.09.2010A micromechanical damage simulation of dual phase steels using XFEM and cohesive elementsNapat Vajragupta, V. Uthaisangsuk, Benjamin Schmaling, Sebastian Münstermann, Alexander Hartmaier, Wolfgang Bleck
The 20th International Workshop on Computational Mechanics of Materials 2010, Loughborough, United Kingdom, September 8-10, 2010
Education
Dr.-Ing. RWTH Aachen University, Germany
M.Sc. RWTH Aachen University, Germany
B.Eng. Chulalongkorn University, Thailand