研究成果

学術論文（査読付き）2015年以降

2024年

Effects of cutting conditions on materials properties of austenitic stainless steels
R. Kondo, M. Okayasu, H. Wen, J. Kawasaki
Journal of Engineering Research

Hydrogen Embrittlement of Austenitic Stainless Steels with Different Surface Treatments
M. Okayasu, H. Wen, R. Kondo
International Journal of Steel Structures

Hydrogen Embrittlement Characteristics of Low Carbon Steels After Heat and Surface Treatments
M. Okayasu, T. Kokado
Transactions of the Indian Institute of Metals

Hydrogen Embrittlement Characteristics of a Die-Casting Die after a High-Pressure Die-Casting Operation
M. Okayasu, K. Shigematsu
International Journal of Metalcasting 18(1) 810-820

Fatigue Limit Diagram for Ferritic Stainless Steels Subjected to Excess Deformation under Fixed Maximum Stress Conditions
M Hayashi, T Ando, R Gonda, K Kitabatake, J Arakawa, H Akebono
MATERIALS TRANSACTIONS 65 (5), 512-517

Relationship between weld rip diameter and fatigue fracture mode for friction stir spot welded tension‐peel joints
M Hayashi, I Fujita, T Itadani, J Arakawa, Y Aoki, H Fujii, H Akebono
Fatigue & Fracture of Engineering Materials & Structures

Estimation of the fatigue crack initiation site and life of Ti-6Al-4V alloy for two types of circle and slender crystal grains
J Arakawa, Y Kawahara, Y Kimura, S Hashimoto, H Akebono, A Sugeta
International Journal of Fatigue 181, 108097

Molding and structure Co-analysis of injection molding composites considering heterogeneity in the thickness direction
C Kawamura, Y Morita, M Fukahori, M Honda, J Arakawa, H Akebono
Materials Transactions 65 (2), 184-193

2023年

An Edge Device Framework in SEMAR IoT Application Server Platform
Y.Y.F. Panduman, N. Funabiki, S. Ito, R. Husna, M. Kuribayashi, M. Okayasu, J. Shimazu, S. Sukaridhoto
Information 14 (6), 312

Hydrogen Embrittlement Characteristics of the Hot- and cold-stamped 22MnB5 Steel
M Okayasu, Y Tanaka
International Journal of Fracture, in press

Material properties of Japanese and Western wooden nails
M Okayasu, K Uotani, T Tanaka
Materialia (Elsevier) 28, 101717

Effects of Artificial Agingon Material Properties of Die-Cast Al-Si-Cu-Mg-xNa Alloy
N. Sahara, R. Ikeda, S. Wu, M. Okayasu
INTERNATIONAL JOURNAL OF METALCASTING 17(1) 515-525

Microstructural Control and Alloy Design for Improving the Resistance to Delayed Fracture of Ultrahigh-Strength Automotive Steel Sheets
T. Senuma, M. Okayasu, H. Mohrbacher
Metals 13(8)

Structural Changes due to Heating and Stress Loading of Metastable Quenched Martensite Structures in Ti–(10–20) mass% Nb Alloys
Y. Mantani, Y. Takemoto
Materials Transactions, 64 (1), 78-85

Self-organized vertical multilayer structures in spinodally decomposed TiO2-VO2 films on glass substrates
Y. Muraoka, K. Takeda, Y. Takemoto, T. Wakita, T. Yokoya
Thin Solid Films 769 139749-139749 2023年3月

Effect of pre-water immersion period on fatigue resistance of adhesive bonded thin steel
J Arakawa, W Jinnouchi, H Akebono, A Sugeta
Int. J. Fatigue 174 107725

Combined effect of surface morphology and residual stress induced by fine particle and shot peening on the fatigue limit for carburized steels
S Kikuchi, K Minamizawa, J Arakawa, H Akebono, S Takesue, M Hayakawa
International Journal of Fatigue 168 107441

Axial compression characteristic of hollow auxetic cylinder lattice structures
Q. Li, X. Li, L. Zhan,T. Zou, X. Chen, X. Lu
Mechanics of Advanced Materials and Structures, in press

Ti-10V-2Fe-3Al合金の焼戻しに伴う組織変化と形状変化
竹元嘉利
チタン 71(3) 204-207

過大変形を受けたフェライト系ステンレス鋼における最大応力固定条件下での疲労限度線図
林 美佑, 安藤 武史, 權田 良平, 北畠 啓史, 荒川 仁太, 曙 紘之, 菅田 淳
材料 72(7) 535-541

射出成形複合材の繊維配向の不均質性を考慮した自動車用H型部材の成形-構造連成解析の検討
河村 力, 森田 泰博, 深堀 貢, 本田 正徳, 荒川 仁太, 曙 紘之, 菅田 淳
材料

複合荷重を考慮した自動車用フレームの断面形状の検討について
河村 力, 本田 正徳, 荒川 仁太, 曙 紘之, 菅田 淳
自動車技術会論文集 54(4)

2022年

Effect of carbon nanotubes on the mechanical properties of cast Al–Si–Cu alloys
M Okayasu, S Wu, IU Hasanah
Materials Science and Technology 38 (4), 237-245

Effects of Artificial Aging on Material Properties of Die-Cast Al–Si–Cu–Mg–xNa Alloy
N Sahara, R Ikeda, S Wu, M Okayasu
International Journal of Metalcasting 17 (1), 515-525

Effect of Artificial Aging on the Mechanical and Fatigue Properties of the Hot-Stamped 6022 Aluminum Alloy
M Okayasu, M Okawa
Journal of Materials Engineering and Performance 31, 6386-6394

Effect of the microstructural characteristics of die-cast ADC12 alloy controlled by Na and Cu on the mechanical properties of the alloy
M Okayasu, N Sahara, N Mayama
Materials Science and Engineering: A 831, 142120

Formation Mechanism of Tempering-Induced Martensite in Ti10Mo7Al Alloy
Y. Takemoto, M. Yasuno, M. Ikemoto, H. Ando, I. Shimizu
Materials Transactions 63(4)489-496

Effects of Thermomechanical Processing on Hydrogen Embrittlement Properties of UltraHigh-Strength TRIP-Aided Bainitic Ferrite Steels
T. Hojo, Y. Zhou, J. Kobayashi, K. Sugimoto, Y. Takemoto, A. Nagasaka, M. Koyama, S. Ajito, E. Akiyama
Metals 12(2)269-269

Effect of fiber orientation on the fatigue crack initiation and propagation of glass fiber reinforced plastics
M. Sakai, J. Arakawa, H. Akebono, A. Sugeta, J. Ohshita, H. Tanizawa, K. Shimizu, J. Ogawa
Jounral of Applied Polymer Science

Fatigue limit estimation for carburized steels with surface compressive residual stress considering residual stress relaxation
K. Minamizawa, J. Arakawa, H. Akebono, K. Nambu, Y. Nakamura, M. Hayakawa, S. Kikuchi
International Journal of Fatigue 160

Analysis of Fatigue Crack Propagation Behavior of Structures with One-Sided Welding in Fillet Welded Joint for Load-Carrying Type
T. Abe, J. Arakawa, H. Akebono, A. Sugeta
Materials Transactions 63(7) 1037-1045

Effects of welding defects on the fatigue properties of spot welded automobile steel sheets and the establishment of a fatigue life evaluation method
Y. Ogawa, I. Ohara, J. Arakawa, H. Akebono, A. Sugeta
Welding in the World 66(4) 745-752

An evaluation of fatigue crack initiation in Ti–6Al–4V alloy by Schmid factor
J. Arakawa, H. Sato, R. Handa, Y. Kimura, S. Hashimoto, H. Akebono, A. Sugeta
Materials Science and Technology, in press

2021年

Examination of Hydrogen Diffusivity in Carbon Steels Using a Newly Developed Hydrogen Permeation System
M Okayasu, M Sato
Experimental Mechanics 61 (9), 1443-1453

The effects of the microstructural characteristics of Fe–0.33 C–1.2 Mn–xNb–xMo steels on hydrogen embrittlement fracture
M Okayasu, R Arai, T Senuma
International Journal of Fracture 231 (2), 257-274

Microstructural characteristics of unidirectionally solidified cast Al–Si–Cu alloy
S Wu, M Okayasu, T Kuwada
International Journal of Metalcasting 15 (3), 1073-1083

Hydrogen embrittlement characteristics of hot-stamped 22MnB5 steel
M Okayasu, T Fujiwara
International Journal of Hydrogen Energy 46 (37), 19657-19669

Decarburizing Behavior and Its Effect on Mechanical Properties of Ultrahigh Strength Steel Sheets
K Kuwata, Y Takemoto, M Okayasu, J Bian, T Senuma
ISIJ international 61 (4), 1300-1308

Piezoelectric properties of lead zirconate titanate ceramics at low and high temperatures
M Okayasu, M Okawa
Advances in Applied Ceramics 120 (3), 127-133

Effects of microstructural characteristics on the hydrogen embrittlement characteristics of austenitic, ferritic, and γ–α duplex stainless steels
M Okayasu, T Fujiwara
Materials Science and Engineering: A 807, 140851

A study of the mechanical properties of a Mg-Al-Zn alloy (AZ91) produced via Thixomolding
M Okayasu, T Fukui
International Journal of Material Forming 14 (2), 271-280

Effect of Cooling Rate on the Precipitation Characteristics of Cast Al-Si-Cu Alloy
M Okayasu, N Sahara, M Touda
Archives of Foundry Engineering 21 (6), 55-60

Ti–10Mo–7Al合金の焼戻し誘起マルテンサイトの形成機構
竹元嘉利, 安野実希子, 池本雅基, 安藤寛幸, 清水一郎
日本金属学会誌 85(11)405-412

Extremely Rapid Age Hardening in Ti-5Al-2Fe-3Mo Solution Treated at High α + β Temperature Region
T. Kunieda, Y. Kohigashi, H. Fujii, K. Takahashi, Y. Takemoto
Metallurgical and Materials Transactions A 52(10)4424-4437

超高強度低合金TRIP鋼の疲労特性に及ぼす母相組織と窒素添加の影響
北條 智彦, 小林 純也, 杉本 公一, 竹元 嘉利, 長坂 明彦, 小山 元道, 秋山 英二
鉄と鋼 107(8)672-680

Effects of Matrix Structure and Nitrogen Content on Fatigue Properties of Ultrahigh-Strength Low Alloy TRIP-Aided Steels
T. Hojo, J. Kobayashi,K. Sugimoto, Y. Takemoto, A. Nagasaka, M. Koyama, E. Akiyama
ISIJ International 61(2)591-598

Decarburizing behavior and its effect on mechanical properties of ultrahigh strength steel sheets
K. Kuwada, Y. Takemoto, M. Okayasu, J. Bian, T. Senuma
ISIJ International 61(4)1300-1308

Elucidation of fatigue characteristics and fracture mechanism of friction stir spot-welded tension-shear joint steels
T. Selvaraj, S. Ishida, J. Arakawa, H. Akebono, A. Sugeta, Y. Aoki, H. Fujii
Fatigue & Fracture of Engineering Materials & Structures 44(1) 74-84

2020年

Failure characteristics of PZT ceramic during cyclic loading
M Okayasu, T Ogawa
Journal of Electronic Materials 49 (9), 5534-5541)

Microstructure-dependent hydrogen diffusion and trapping in high-tensile steel
M Okayasu, J Motojima
Materials Science and Engineering: A 790, 139418

The effect of precipitations (NbC and carbide) in Fe–C–Mn-xNb steels on hydrogen embrittlement characteristics
M Okayasu, M Sato, D Ishida, T Senuma
Materials Science and Engineering: A 791, 139598

Hot-stamping technology for carbon fiber reinforced thermoplastic plates based on electrical resistance heating
M Okayasu, M Sato
Journal of composite materials 54 (10), 1353-1361

An Electrical Resistance Joining Technology for Carbon Fiber-Reinforced Polyphenylene Sulfide Composites
M Okayasu, T Kubota
Journal of Materials Engineering and Performance 29 (4), 2134-2143

2019年

Effects of loading contact on electric-power generation of lead zirconate titanate piezoelectric ceramic plate
M Okayasu, T Ogawa
Journal of Advanced Ceramics 8 (4), 509-518

Mechanical and fatigue properties of long carbon fiber reinforced plastics at low temperature
M Okayasu, Y Tsuchiya
Journal of Science: Advanced Materials and Devices 4 (4), 577-583

Effect of microstructural characteristics on mechanical properties of ferritic stainless steel
M Okayasu, T Shigeoka
Journal of Materials Engineering and Performance 28 (11), 6771-6778

Fatigue Failure Characteristics of Single-Crystal Fe-3% Al Alloy
M Okayasu, K Noda
Journal of Materials Engineering and Performance 28 (10), 5978-5987

EStructural health monitoring system for remote inspection of material failure
M Okayasu, T Yamasaki
Journal of Nondestructive Evaluation 38 (2), 1-6

Influence of microstructure on the mechanical properties and hydrogen embrittlement characteristics of 1800 MPa grade hot-stamped 22MnB5 steel
M Okayasu, L Yang
Journal of Materials Science 54 (6), 5061-5073

Effect of microstructural characteristics on mechanical properties of austenitic, ferritic, and γ-α duplex stainless steels
M Okayasu, D Ishida
Metallurgical and Materials Transactions A 50 (3), 1380-1388

Experimentally and Numerically Analyzed Piezoelectric Characteristics of PZT Ceramics
L Yang, H Nagano, M Okayasu
Journal of Materal Science Research 8 (1), 10-16

超高強度ホットスタンピング材の耐遅れ破壊性向上の組織制御
瀬沼武秀, 竹元嘉利, 北條智彦
鉄と鋼 105(2)51-59

Ti-10Mo-7Al合金の奇妙な相変態
竹元嘉利
チタン 67(2)112-115

2018年

Fatigue properties of a nanocrystalline titanium based bulk metallic glassy alloy
M Okayasu, T Shigeoka
Journal of Science: Advanced Materials and Devices 3 (4), 478-484

Method for reducing aluminum alloy heat loss in high pressure die casting shot sleeves
M Okayasu, S Wu, T Hirayama
International Journal of Cast Metals Research 31 (5), 308-316

Tensile properties of unsaturated polyester and epoxy resin reinforced with recycled carbon-fiber-reinforced plastic
M Okayasu, Y Kondo
Applied Composite Materials 25 (3), 561-568

Corrosion characteristics of a tungsten alloy die-casting mould material in molten aluminium alloy
M Okayasu, L Yang
International Journal of Cast Metals Research 31 (3), 162-168

Mechanical Properties of Cast Al-Mg5 Alloy Produced by Heated Mold Continuous Casting
M Okayasu, S Takeuchi
International Journal of Metalcasting 12 (2), 298-306

Domain switching behavior in lead zirconate titanate piezoelectric ceramics
M Okayasu, K Bamba
Scripta Materialia 146, 272-275

Mechanical properties of the riveted connecting forming of CFRP plates
M Okayasu, R Naito
International Journal of Material Forming 11 (2), 225-232

Effects of machined circular holes on the mechanical properties of unidirectional carbon fiber-reinforced plastics
M Okayasu, R Naito, D Fukuyama, K Ogi
Journal of Composite Materials 52 (4), 465-474

圧電セラミックスの90°ドメインスイッチング特性に及ぼす熱応力の影響
馬場 康平, 岡安 光博
日本機械学会論文集 84 (863)17-00570

Martensitic Transformation Induced in Ti-15V-7Al Alloy at Low and High Temperatures
Y. Takemoto, M. Tsunekawa, Y. Manabe, S. Itano and Y. Muraoka
Materials Transactions 59(10)1560-1566

Multilayer formation via spinodal decomposition in TiO2-VO2 epitaxial films on sapphire substrates
Y. Matsuura, F. Yoshii, T. Otsuka, K. Kadowaki, M. Ijiri, Y. Takemoto, K. Terashima, T. Wakita, T. Yokoya and Y. Muraoka
Journal of the European Ceramic Society 38, 5043-5050

Ti-42mass％Nb合金のマルテンサイト変態に伴う電気抵抗変化
竹元嘉利, 丸山拓也, 井尻政孝
日本金属学会誌 82(7)256-261

Ti-15V-7Al 合金の低温と高温で形成されるマルテンサイト変態
竹元嘉利, 恒川弥佑, 真鍋侑司, 板野壮志, 村岡祐治
日本金属学会誌 82(8)307-313

The effects of crystallographic orientation on fatigue crack initiation behavior in Ti-6Al-4V
S. Sasaoka, J. Arakawa, H. Akebono, A. Sugeta, Y. Shirai, E. Nakayama, Y. Kimura
International Journal of Fatigue 117, 371-383

2017年

In situ TEM observations of microstructural characteristics of lead zirconate titanate piezoelectric ceramic during heating to 1000°C
M Okayasu, T Ogawa, Y Sasaki
Ceramics International 43 (18), 16306-16312

High Strength of Mg-9% Al-1% Zn Alloys Achieved by Severe Working
M Okayasu, T Muranaga
Journal of Materials Engineering and Performance 26 (10), 4977-4989

Mechanical properties of Al–Si–Cu Alloys produced by the continuous casting process with heating process
M Okayasu, S Takeuchi, T Ochi
International Journal of Cast Metals Research 30 (4), 217-225

Effects of 90 domain switching on electric generation properties of PZT ceramic
M Okayasu, T Yamasaki
Ceramics International 43 (4), 3590-3600

Analysis of microstructural effects on mechanical properties of copper alloys
M Okayasu, T Muranaga, A Endo
Journal of Science: Advanced Materials and Devices 2 (1), 128-139

Effects of Oxide Scale on the Corrosion and Mechanical Properties for a High Speed Steel and a Graphite Cast Iron
M Okayasu, S Wu
Oxidation of Metals 87 (1), 159-178

Phase transformation system of austenitic stainless steels obtained by permanent compressive strain
M Okayasu, S Tomida
Materials Science and Engineering: A 684, 712-725

Domain switching characteristics of lead zirconate titanate piezoelectric ceramics on a nanoscopic scale
M Okayasu, K Bamba
Journal of the European Ceramic Society 37 (1), 145-159

Effect of aliovalent dopants on the kinetics of spinodal decomposition in rutile-type TiO2-VO2
M. Ogata, K. Kadowaki, M. Ijiri, Y. Takemoto, K. Terashima, T. Wakita, T. Yokoya, Y. Muraoka
Journal of the European Ceramic Society, International Journal of High Technology Ceramics 37(9) 3177-3183

Stress-Strain Behavior of Ti-Nb Alloys under Compressions along Linear Strain Paths and Bilinear Plane Strain Path
I. Shimizu, Y. Takkemoto, S. Ishikawa, T. Kumura
Advanced Experimental Mechanics (2) 99-104

2016年

A study of the electric power generation properties of a lead zirconate titanate piezoelectric ceramic
M Okayasu, K Watanabe
Ceramics International 42 (12), 14049-14060

Mechanical properties of austenitic stainless steel with high niobium contents
M Okayasu, S Wu, K Noda, DY Lin, SM Yang
Materials Science and Technology 32 (13), 1382-1394

Effects of Sb, Sr, and Bi on the material properties of cast Al-Si-Cu alloys produced through heated mold continuous casting
M Okayasu, S Takeuchi, S Wu, T Ochi
Journal of Mechanical Science and Technology 30 (3), 1139-1147

Precise analysis of compressive strain effects on electric power generation properties of a lead zirconate titanate piezoelectric ceramic
M Okayasu, K Watanabe
Journal of Advanced Ceramics 5 (1), 35-39

Mechanical properties and failure characteristics of cast and extruded Mg97Y2Zn1 alloys with LPSO phase
M Okayasu, S Takeuchi, M Matsushita, N Tada, M Yamasaki
Materials Science and Engineering: A 652, 14-29 26

Mechanical Properties of Magnesium Alloys Produced by the Heated Mold Continuous Casting Process
M Okayasu, S Wu, T Tanimoto, S Takeuchi
Archives of Foundry Engineering 16 (4), 208-216

Ti-35Nb-7Al合金の焼戻しに伴う相変態挙動
井尻政孝,富田悠希,石川高史,竹元嘉利
日本金属学会誌 80(9) 547-552

Ti-4Fe-7Al合金の溶体化塩浴焼入れによる微細組織
井尻政孝, 奥村輝,石川高史,門脇賢司,竹元嘉利
日本金属学会誌 80(11) 691-696

Oil-in-water emulsion as fabrication platform for uniform plasmon-controlled two-dimensional metallic nanoparticle array
R. Kagawa, N. Takeyasu, T. Kaneta, Y. Takemoto
Applied Physics Express 9(7) 075003

2015年

The electric power generation characteristics of a lead zirconate titanate piezoelectric ceramic under various cyclic loading conditions
M Okayasu, K Watanabe
Ceramics International 41 (10), 15097-15102

The effects of defects on tensile properties of cast ADC12 aluminum alloy
M Okayasu, H Sakai
Metallurgical and Materials Transactions A 46 (11), 5418-54305

Effects of cyclic loading on fatigue properties of austenite stainless steel
M Okayasu, H Fukui
Journal of Mechanical Science and Technology 29 (9), 3663-3668

Material properties of various cast aluminum alloys made using a heated mold continuous casting technique with and without ultrasonic vibration
M Okayasu, Y Miyamoto, K Morinaka
Metals 5 (3), 1440-1453

Precise analysis of effects of aging on mechanical properties of cast ADC12 aluminum alloy
M Okayasu, S Go
Materials Science and Engineering: A 638, 208-218

Crystallization characteristics of cast aluminum alloys during a unidirectional solidification process
M Okayasu, S Takeuchi
Materials Science and Engineering: A 633, 112-120

Influence of solidification rate on material properties of cast aluminium alloys based on Al–Si–Cu and Al–Si–Mg
M Okayasu, S Yoshida
International Journal of Cast Metals Research 28 (2), 105-116

Precise analysis of microstructural effects on mechanical properties of cast ADC12 aluminum alloy
M Okayasu, S Takeuchi, M Yamamoto, H Ohfuji, T Ochi
Metallurgical and Materials Transactions A 46 (4), 1597-1609

Mechanical properties of Samurai swords (carbon steel) made using a traditional steelmaking technology (tatara)
M Okayasu, H Sakai, T Tanaka
Journal of Material Sciences & Engineering 4 (2), 1-6

Ti-Nb 合金における焼入れマルテンサイトの変形に伴う結晶構造と材料特性の変化
万谷義和,竹元嘉利
日本金属学会誌 79(9) 461-467

Ti-10Mo-7Al合金の熱処理に伴う相変態挙動
井尻政孝,竹元嘉利
日本金属学会誌 79(9) 468-473