Professor SHIMOKAWA Tomotsugu
Faculty, Affiliation
Faculty of Mechanical Engineering, Institute of Science and Engineering
College and School Educational Field
Division of Mechanical Science and Engineering, Graduate School of Natural Science and Technology
Division of Mechanical Science and Engineering, Graduate School of Natural Science and Technology
Course in Mechanical Sciences, School of Mechanical Engineering, College of Science and Engineering
Laboratory
Mechanism Design TEL:076-234-4692 FAX:076-234-4692
Academic Background
【Academic background(Doctoral/Master's Degree)】
Osaka University Doctor Graduate School, Division of Engineering 200203 Completed
Osaka University Master Graduate School, Division of Engineering 200003 Completed
【Academic background(Bachelor's Degree)】
Osaka University 199803
Career
Kanazawa University(2003/04/01-2006/09/30)
Research Associate, Graduate School of Natural Science and Technology, Kanazawa University(2004/04/01-2006/09/30)
Lecturer, Graduate School of Natural Science and Technology, Kanazawa University(2006/10/01-2009/03/31)
Associate Professor(2009/04/01-)
Year & Month of Birth
1974/08
Academic Society
Japan Society for Design Engineering
Award
○Best Poster Award, International Symposium on Giant Straining Process for Advanced Materia(2010/11/01)
○JSME Young Engineers Award(2010/04/23)
○TMSJ 2008 Best paper award
○JSME Materials & Mechanics Division Awards for best presentation(1999/10)
○JSME Kansai Branch 1998, Best Presentation Awards(1998/03/22)
○JSMS Committee on Molecular Dynamics Simulation Award for best presentation(2006/05/26)
○JSMS Award for Promising Researchers(2007/05/19)
○JSMS Award for Scientific Papers(2006/05)
Specialities
Materials/Mechanics of materials
Speciality Keywords
Research Themes
Development of Multi-Scale Atomic Simulation Method
Development of models specific to each purpose is needed to computer-simulate mechanical characteristics and deformation- fracture mechanisms of materials. Atomic simulation is one of the effective means of expression with which heterogeneous structure and regional deformation can be expressed because it deals directly with each atom, but it requires an enormous degree of freedom because it deals with each atom even in defect-independent areas where change in deformation gradient is small. In addition, since there is a limit to the number of computable atoms, boundary conditions have a significant impact on analysis results. We are developing multiscale models to address these problems.
Study on Unique Mechanical Properties of Nanostructured Materials
It has been reported that nanocrystals, formed with a diameter of several hundred nanometers, show mechanical properties that are different from those of typical coarse particles. The reason for this could be that the intergranular volume fraction increases rapidly. Also, it is impossible to deal with grain rotation and grain collective behavior that derive from interactions of multiple defective structures only with an understanding of each defective property, and the selection of representative volume elements to consider is crucial. I develop nanocrystal models that consist of multiple crystal grains using the molecular dynamics method directly in the computer, conduct computer experiments, and thereby examine strong grain size dependence and grain boundary properties dependence.
Evolution and Structural Change of Lattice Defects using Atomic Scale Computational Experiments
The strength of metallic crystal materials is closely related to their inner structure (crystal region and defect region). The defect region can be considered to include a 0-dimensional point defect (for example, a hole), a 1-dimensional line defect (dislocation), and a 2-dimensional planar defect (grain boundary). It is difficult to understand the interactions of these defective structures through experimental and theoretical approaches, and atomic simulation with which each defective structure can be directly expressed can be an effective tool. Currently, I am conducting research on the interactions between dislocation and grain boundary, the defective structure development mechanism that is unique to nanocrystals, and the grain subdivision mechanism that is presumably developed by collective dislocation behavior.
Books
- Tomotsugu Shimokawa Part II Simulation of Plaston and Plaston Induced Phenomena: 3. Atomistic Study of Disclinations in Nanostructured Metals, in “The Plaston Concept - Plastic Deformation in Structural Materials”, Edited by Isao Tanaka, Nobuhiro Tsuji, Haruyuki Inui Springer 2022/01/26
Papers
- Heterogeneous evolution of lattice defects leading to high strength and high ductility in harmonic structure materials through atomic and dislocation simulations T. Shimokawa, T. Hasegawa, K. Kiyota, T. Niiyama, K. Ameyama Acta Materialia 226 117679(1-15) 2022/01/20
- A novel work hardening mechanism of nanoscale materials by grain boundary transformation T. Shimokawa, T. Niiyama, T. Miyaki, M. Ikeda, K. Higashida Acta Materialia 224 117536(1-14) 2021/12/04
- Molecular Dynamics Simulation of the Effect of Cementite Decomposition on Yield Phenomena in Pearlite Microstructure Tomotsugu Shimokawa, Takumi Oto, Tomoaki Niiyama ISIJ International 62 2 343-352 2021/08/27
- Investigating the dislocation reactions on Σ3{111} twin boundary during deformation twin nucleation process in an ultrafine‐grained high‐manganese steel C.Y. Hung, T. Shimokawa, Y. Bai, N. Tsuji, M. Murayama Scientific Reports 11 19298(1-13) 2021/09/29
- A correlation between grain boundary character and deformation twin nucleation mechanism in coarse‐grained high‐Mn austenitic steel C.Y. Hung, Y. Bai, T. Shimokawa, N. Tsuji, M. Murayama Scientific Reports 11 8468(1-13) 2021/04/19
- Dislocation Emission from Grain Boundaries in High-Entropy Alloys: Influence of Atomic Composition at Grain Boundaries Kohei Shiotani, Tomoaki Niiyama, Tomotsugu Shimokawa Materials Transactions 61 7 1272 2020/06/25
- A Mechanism of Carbon-Cluster Strengthening through Atomic Simulations Tomotsugu Shimokawa, Kiichiro Yasui, Tomoaki Niiyama, Keisuke Kinoshita, Hideaki SawadaTomotsugu Shimokawa, Kiichiro Yasui, Tomoaki Niiyama, Keisuke Kinoshita, Hideaki Sawada Materials Transactions 61 11 2139 2020/09/29
- A Mechanism of Carbon-Cluster Strengthening though Atomic Simulations Tomotsugu Shimokawa, Kiichiro Yasui, Tomoaki Niiyama, Keisuke Kinoshita, Hideaki Sawada 84 1 19-27 2019/11/05
- Dislocation emission from grain boundaries in high-entropy alloys: Influence of atomic compositions at grain boundaries Tohei Shiotani, Tomoaki Niiyama, Tomotsugu Shimokawa 69 2 141-149 2020/02/20
- Structural relaxation affecting shear-transformation avalanches in metallic glasses Tomoaki Niiyamai, Masato Wakeda, Tomotsugu Shimokawa and Shigenobu Ogata Physical Review E 100 043002 2019/10/02
- Crystal Plasticity Analysis on Ductility of Ferrite/Cementite Multilayers: Effect of Dislocation Absorption Ability of the Hetero Interface Y. Yasuda, T. Shimokawa, T. Ohashi, T. Niiyama Tetsu-to-Hagané 105 2 24-32 2018/11/01
- Interfacial-dislocation-controlled deformation and fracture in nanolayered composites: Toward higher ductility of drawn pearlite T. Shimokawa, T. Niiyama, M. Okabe, J. Sawakoshi Acta Materialia 164 602-617 2018/11/10
- Strain-hardening characteristics of ferrite layers in pearlite microstructure Yasuda Yasuda, Tetsuya Ohashi, Tomotsugu Shimokawa, Tomoaki Niiyama Materials Science and Technology 8 pages 2017/11/09
- Barrier effect of grain boundaries on the avalanche propagation of polycrystalline plasticity Tomoaki Niiyama, Tomotsugu Shimokawa Physical Review B 94 140102(R)(1-5) 2016/10/25
- Atomic Scale Simulations of Relationship between Macroscopic Mechanical Properties and Microscopic Defect Evolution in Ultrafine-grained Metals Tomohito Tsuru, Yoshiteru Aoyagi, Tomotsugu Shimokawa Materials Transactions 57 9 1476-1481 2016/07/24
- Grain Subdivision Mechanism Related to Partial Disclinations in Severe Plastic Deformation: A Molecular Dynamics Study Tomotsugu Shimokawa, Tomoaki Yamashita, Tomoaki Niiyama, Nobuhiro Tsuji Materials Transactions 57 9 1392-1398 2016/08/25
- Heterogeneous plastic deformation and Bauschinger effect in ultrafine-grained metals: atomistic simulations Tomohito Tsuru, Yoshiteru Aoyagi, Yoshiyuki Kaji, Tomotsugu Shimokawa Modelling and Simulation in Materials Science and Engineering 24 035010(1-10) 2016/02/22
- Effect of Loading Condition on Statistics of Intermittent Plasticity in Metallic Crystals Tomoaki Niiyama, Tomotsugu Shimokawa 65 2 119-126 2016/02/01
- Influence of competition between intragranular dislocation nucleation and intergranular slip transfer on mechanical properties of ultrafine-grained metals T. Tsuru, Y. Aoyagi, Y. Kaji, T. Shimokawa Materials Transactions 54 9 1580-1586 2013/05/17
- Influence of non-glide stresses on the peierls energy of screw dislocations K. Kinoshita, T. Shimokawa, T. Kinari, H. Sawada, K. Kawakami, K. Ushioda Transactions of the JSME 80 809 CM0018(1-10) 2014/01/25
- A multiscale approach for the deformation mechanism in pearlite microstructure: Numerical evaluation of elasto-plastic deformation in fine lamellar structures T. Ohashi, L. Roslan, K. Takahashi, T. Shimokawa, M. Tanaka, and K. Higashida Materials Science and Engineering: A 588 214-220 2013/12/20
- Influence of Competition between Intragranular Dislocation Nucleation and Intergranular Slip Transfer on Mechanical Properties of Ultrafine-Grained Metals T. Tomohito, Y. Aoyagi, Y. Kaji, T. Shimokawa JOURNAL OF THE JAPAN INSTITUTE OF METALS 78 1 45-51 2014/01/01
- Atomistic mechanisms of intermittent plasticity in metals: Dislocation avalanches and defect cluster pinning T. Niiyama, T. Shimokawa Physical Review E 91 2 022401(1-6) 2015/01/01
- A multiscale approach for the deformation mechanism in pearlite microstructure: Experimental measurements of strain distribution using a novel technique of precision markers M. Tanaka, Y. Yoshimi, K. Higashida, T. Shimokawa, T. Ohashi Materials Science and Engineering: A 590 37-43 2014/01/10
- Dislocation multiplication from the Frank-Read source in atomic models T. Shimokawa, S. Kitada Materials Transactions 55 1 58-63 2013/11/29
- A multiscale approach for the deformation mechanism in pearlite microstructure: Atomistic study of the role of the heterointerface on ductility T. Shimokawa, T. Oguro, M. Tanaka, K. Higashida, and T. Ohashi Materials Science and Engineering: A 598 68-76 2014/03/26
- Atomic-scale intergranular crack-tip plasticity in tilt grain boundaries acting as an effective dislocation source T. Shimokawa, M. Tsuboi Acta Materialia 87 233-247 2015/04/01
- Matching conditions in the quasicontinuum method: Removal of the error introduced at the interface between the coarse-grained and fully atomistic region T. Shimokawa, J. J. Mortensen, J. Schiltz, K. W. Jacobsen Physical Review B 69 21 214104(1-10) 2004/06
- Change of Load with Time for Laterally Compressed Filament Yarn R. Ishihara, K. Ohta, T. Shimokawa and T. Kinari 2005/08
- Observation of Heald Motion during Shedding Motion in Jet Loom Y. Mochizuki, T. Akamura, T. Shimokawa and T. Kinari 2005/08
- Reduction of Collision Sound during Shedding Motion in Jet Loom by Using Commercial Plastic Heald T. Kinari, D. Mori, T. Shimokawa and S. Shintaku 2005/08
- Atomistic Simulations of Interface Properties in Metals T. Shimokawa 2007/04
- Influence of the grain boundary structure on the crystal slip transmission by the quasicontinuum simulations T. Shimokawa, T. Kinari and S. Shintaku 2005/12
- Atomistic Study of Plastic Deformation of Nanostructured Materials Akihiro Nakatani and Tomotsugu Shimokawa 2005/10
- Temperature Dependence of a Grain Size of the Maximum Strength of Nanocrystalline Metals by Molecular Dynamics Simulation T. Shimokawa, T. Kinari, S. Shintaku, A. Nakatani and H. Kitagawa 2005/01
- A seamless coupling of atomistic and continumm fields in the quasicontinuum method T. Shimokawa, J. Schiotz, J. J. Mortensen and K. W. Jacobsen 2005/10
- Deformation and Fracture Mechanism of Round Bar Specimen of Nanocrystalline Materials by Molecular Dynamics Simulation Tomotsugu. Shimokawa, Akihiro. Nakatani and Hiroshi. Kitagawa 2002/07
- Molecular Dynamics Simulation on Mechanical Properties and Internal Structures of Nano-Crystalline Materials under Different Loading Processes Tomotsugu. Shimokawa, Akihiro. Nakatani and Hiroshi. Kitagawa 2001/05
- Grain Boundary Characteristics of Nano-Polycrystalline Materials using Molecular Dynamics Simulation Tomotsugu. Shimokawa, Akihiro. Nakatani and Hiroshi. Kitagawa 2001/02
- Meso-Plasticity Study for Polycrystalline Material (Atomistic Simulation of Nano-Crystal) Tomotsugu. Shimokawa, Akihiro. Nakatani and Hiroshi. Kitagawa 1999/07
- Yarn Path on a Mold for Double Sheet Bend Knotter KIKURA Hirotaka, SHINTAKU Sukenori, KINARI Toshiyasu, SHIMOKAWA Tomotsugu 54 3 93-101 2008/05
- Designing Yarn Path on a Mold for Knot Formation KIKURA Hirotaka, SHINTAKU Sukenori, KINARI Toshiyasu, SHIMOKAWA Tomotsugu 54 3 83-91 2008/05
- Analyzing the Path and the Tension of a Yarn under a False-twist Process Using a Doubly Stacked Multi-disk Spindle KANEDA Naoto, SHINTAKU Sukenori, KINARI Toshiyasu, SHIMOKAWA Tomotsugu 53 5 203-210 2007/09
- Jumping Behavior of Heald in a Shedding Motion of Loom AKAMURA Taketo, KINARI Toshiyasu, SHIMOKAWA Tomotsugu, MIYASHITA Daisuke, MOCHIZUKI Yoshikazu, SHINTAKU Sukenori 52 2 87-92 2006/02
- Curve Drawn by Yarn Traveling on a Cylindrical Surface KINARI Toshiyasu, SHINTAKU Sukenori and SHIMOKAWA Tomotsugu 58 8 95-100 2005/08
- Relationship between grain boundary structures and mechanical properties of nanocrystalline metals with different stacking fault energy using atomic scale computational experiments Tomotsugu SHIMOKAWA, Toshiyasu KINARI, Sukenori SHINTAKU 57 8 761-767 2008/08
- Brittle-ductile transition in low carbon steel deformed by the accumulative roll bonding process Masaki Tanaka, Kenji Higashida, Tomotsugu Shimokawa, Tatsuya Morikawa 50 1 2009/01
- Mesh Refinement with Elastic Stiffness Coefficients in the Quasicontinuum Model 74 738 2008/02
- Atomic simulations on the grain subdivision of a crystalline metal Toshiyasu Kinari, Sukenori Shintaku 561 1983-1986 2007/11
- Energetic Study on Defect Structures in Nanocrystalline Aluminum and Copper by Atomic Simulations 56 11 1068-1075 2007/11
- Interaction mechanism between edge dislocations and asymmetrical tilt grain boundaries investigated via quasicontinuum simulations Toshiyasu Kinari, Sukenori Shintaku 75 2007/04
- Dislocation-Grain Boundary Interactions by the Quasicontinuum Method T. Kinari and S. Shintaku 340 341 973-978 2007/01
- Microstructural evolution in crystalline metal induced by plastic deformation---Atomistic study of grainsubdivision in tension, torsion and rolling--- 144 1 25-35 2007/01
- Collective grain deformation of nanocrystalline metals by molecular dynamics simulations T. Kinari, S. Shintaku and A. Nakatani 14 5 63-72 2006/05
- Defect-induced anisotropy in mechanical properties of nanocrystalline metals by molecular dynamics simulations T. Kinari, S. Shintaku, A. Nakatani and H. Kitagawa 13 8 1217-1231 2005/10
- Grain-size dependence of the relationship between intergranular and intragranular deformation of nanocrystalline Al by molecular dynamics simulations 71 22 224110 2005/06
- The Effect of Severe Plastic Deformation on the Brittle-Ductile Transition in Low Carbon Steel Masaki Tanaka, Kenji Higashida, Tomotsugu Shimokawa MATERIALS SCIENCE FORUM 633-634 471-480 2009/09
- Mechanical Properties Depending on Grain Sizes of Fcc Nanocrystalline Metals by Using Molecular Dynamics Simulation (Investigation of Stacking Fault Energy's Influence) JSME INTERNATIONAL JOURNAL SERIES A-SOLID MECHANICS AND MATERIAL ENGINEERIN 47 2 83-91 2004/04
- Atomistic Study on Ideal Strength of Nanocrystal and Deformation Induced Nanostructures Mesoscopic Dynamics of Fracture Process and Materials Strength 365-380 2004/07
- Adaptive Mesh Refinement with Elastic Stiffness Coefficients in the Quasicontinuum Model T. Shimokawa, T. Kinari, and S. Shintaku 3 2 408-416 2009/07
- Effect of Extrinsic Grain Boundary Dislocations on Mechanical Properties of Ultrafine-Grained Metals by Molecular Dynamics Simulations Tomotsugu Shimokawa, Toshiyasu Kinari, Sukenori Shintaku MATERIALS TRANSACTIONS JIM 50 1 2009/01
Conference Presentations
- Dynamic grain boundary segregation and atom drag in high-entropy alloys(conference：MRM2021)(2021/12/15)
- in situ TEM to investigate correlations between microstructure characteristics and deformation twin nucleation mechanisms in high manganese austenitic TWIP steel (II)(conference：MRM2021)(2021/12/15)
- in situ TEM to investigate correlations between microstructure characteristics and deformation twin nucleation mechanisms in high manganese austenitic TWIP steel (I)(conference：MRM2021)(2021/12/15)
- Lattice Defect Development in Harmonic Metals through Atomic Simulations(conference：TMS2021 VIRTUAL)(2021/03/17)
- Relationship between the development of lattice defects and mechanical properties in solid materials through atomic simulations(2020/09/07)
- Influence of Misfit Dislocations on Mechanical Properties of Fine Pearlite(conference：2017 MRS Fall Meeting)(2017/12/01)
- Influence of interfacial dislocation spacings on strength of pearlite microstructure: A molecular dynamics simulation(conference：2nd International Hetero-Structure Materials Workshop, Hetero 2017)(2017/10/30)
- Influence of dislocation mean free path on strain-hardening rate in multi-layered microstructure: crystal plasticity analysis(conference：The 15th International Conference on Advanced Materials, IUMRS-ICAM2017)(2017/08/29)
- Atomic simulation of the influence of hetero-interface structures on mechanical properties of fine pearlite(conference：The 15th International Conference on Advanced Materials, IUMRS-ICAM2017)(2017/08/29)
- Atomic Simulations for the Interraction between Grain Boundaries and Avalanche Motion of Dislocations(conference：Dislocations 2016)(2016/09/19)
- Influence of Annealing on Dislocation Emission from Non-equilibrium Grain Boundaries(conference：Asia-Pacific Conference on Fracture and Strength (APCFS2016))(2016/09/20)
- Atomic Simulation of Hetero-Interface Mediated Plastic Deformation in Pearlitic Steel(conference：9th Pacific Rim International Conference on Advanced Materials and Processing (PRICM9))(2016/08/02)
- A molecular dynamics study of intermittent plastic deformation in metals(conference：Workshop on Deformation, Damage and Life Prediction of Structural Materials)(2014/08/23)
- Atomic simulation of lattice defect interactions in nanostructured materials(conference：RIMS International Conference, "Mathematical Challenge to a New Phase of Materials Science")(2014/08/05)
- Intermittent plasticity dominated by defect cluster pinning(conference：RIMS International Conference, "Mathematical Challenge to a New Phase of Materials Science")(2014/08/05)
- Atomic simulation of the role of the interface on mechanical properties of pearlite steel(conference：The 4th International Symposium on Steel Science- ISSS 2014)(2014/11/06)
- Atomic Scale Investigation of Intermittent Plasticity by Molecular Dynamics Simulations(conference：Complexity in Mechanics: Intermittency and Collective Phenomena in Disordered Solids)(2014/10/22)
- Influence of Grain Boundary Dislocation Sousrces on Mechanical Properties of Nanostructured Metals: A Molecular Dynamics Study(conference：The 2nd International Workshop on Bulk Nanostructured Metals)(2015/08/04)
- Large-Scale Atomistic Simulations of Anisotropic Plastic Deformation in Bulk Nanostructuerd Metals(conference：The 2nd International Workshop on Bulk Nanostructured Metals)(2015/08/04)
- Multiscale Modeling and Crystal Plasticity Simulation on Anisotropic Yielding Behavior of Bulk Nanostructured Metals(conference：The 2nd International Workshop on Bulk Nanostructured Metals)(2015/08/04)
Others
Arts and Fieldwork
Patent
Theme to the desired joint research
Grant-in-Aid for Scientific Research
○「バルクナノメタル新学術領域研究の連携的な運営と統括」(2010-2015)
○「粒界性格を制御した金属材料設計・開発に関する原子シミュレーションによる基礎的研究」(2004-2006)
○「結晶・非晶質構造体の局所塑性変形の連結・伝ぱメカニズムに関する原子・分子論的研究」(2007-2009)
○「高密度格子欠陥を有する物質・材料のマイクロダイナミクス解析」(2006-2008)
○「内部欠陥構造発展の大規模計算によるバルクナノメタルの力学特性解析」(2010-2014)
○「ナノスケール複合材料中の格子欠陥力学場解析」(2012-2014)
Competitive research funding,Contribution
Collaborative research,Consignment study
Classes (Bachelors)
○Strength of Materials IIA(2017)
○Strength of Materials IIB(2017)
○Introduction to Micro-/Nano-Mechanics(2017)
○Field Exercise for Technical Intern A(2017)
○Field Exercise for Technical Intern B(2017)
○Field Exercise for Technical Intern B(2017)
○Mechanical Analysis of Solids(2017)
○Mechanical Engineering Design and Drawing(2017)
○Thesis Report(2016)
○Thesis Report(2016)
○Seminar in Mechanical Engineering(2016)
○Strength of Materials II(2016)
○Mechanical Engineering Design and Drawing(2016)
○Introduction to Micro-/Nano-Mechanics(2016)
○Mechanical Analysis of Solids(2016)
Classes (Graduate Schools)
○Computational Mechanics of Materials(2017)
○Advanced Computational Mechanics of Materials(2017)
○Advanced Computational Mechanics of Materials(2017)
○Advanced Computational Mechanics of Materials(2017)
○Advanced Computational Mechanics of Materials(2017)
○Topics in Mechanical Sciences 3(2017)
○Topics in Mechanical Sciences 2(2017)
○Exercise in Mechanical Engineering(2017)
○Mechanics of Materials and Theory of Elasticity(2017)
○Master Thesis Report(2017)
○Master Thesis Report(2017)
○Mathematics in Cryptography A(2016)
○Exercise in Mechanical Engineering(2016)
○Master Thesis Report(2016)
○Master Thesis Report(2016)
○Mechanics of Materials and Theory of Elasticity(2016)
○Computational Mechanics of Materials(2016)
○Advanced Computational Mechanics of Materials(2016)