Updated on 2024/03/28

写真a

 
ASAKAWA, Moto
 
Affiliation
Faculty of Science and Engineering
Job title
Professor Emeritus
Degree
Doctor ( Waseda University )

Research Experience

  • 1996.04
    -
     

    Waseda University   School of Science and Engineering

  • 1968
    -
    1996

    Sumitomo Metals Co.,Ltd.(1968-1996), Prof.(1996-,Waseda)

  • 1992.07
    -
     

    同小倉製鉄所・専門部長

  • 1988.07
    -
     

    同研究開発本部・塑性加工研究部・条鋼研究室(室長)

  • 1987.04
    -
    1988.03

    国士舘大学工学部 機械工学科 非常勤講師(塑性加工)

  • 1978.05
    -
     

    同東京本社・技術開発企画部・開発企画室(主任)

  • 1975.04
    -
     

    同小倉製鉄所・圧延部・棒鋼工場(副工場長)

  • 1968.04
    -
     

    住友金属工業株式会社 中央技術研究所・加工研究室

  • 1966
    -
     

    B.S.(1966,Waseda), M.S.(1968,Waseda), Dr.Engr.(1980,Waseda)

▼display all

Education Background

  •  
    -
    1968

    Waseda University  

  •  
    -
    1968

    Waseda University   Graduate School, Division of Engineering   Mechanical Engineering  

  •  
    -
    1966

    Waseda University   School of Science and Engineering  

  •  
    -
    1966

    Waseda University   Faculty of Science and Engineering   Mechanical Engineering  

Committee Memberships

  • 1996
    -
    Now

    評議員(1996-現在),創形創質副部会長(1998-1999)創形創質部会長(2000-2001)創形創質部会顧問(2002-)

  • 2000
    -
    2007

    日本鉄鋼協会  創形創質部会長(2000-2001),評議員(1996~2007)

  • 2004
    -
     

    日本機械学会  機械材料・材料加工部門長(2004~2005),フェロー(2005~現在),評議員(2006~現在

  • 1997
    -
    2001

    機械材料・加工部門運営委員(1997-2001),同運営委員幹事(2001),同大会実行委員長(1999-2000),ASME/JSME国際会議組織委員(2001-2002)

  • 1997
    -
    1998

    理事(1997-1998),企画委員長(1998),評議員(1989-現在),校閲委員(1995-),人事委員会委員(1990,1992,1999),学会賞審査委員(1997-1999),論文賞推薦委員会委員(1998-2000), 40周年記念事業本部委員(1998-2001),7thICTP組織委員(2001-2002), 50周年記念実行委員長(2008-2011),九州支部幹事(1990-1994),東京支部幹事(2000-2001),伸線技術分会幹事(1988-1990),教育問題研究会委・・・

  • 1997
    -
     

    日本塑性加工学会  理事(1997-1998),評議員(1996~現在),フェロー(2003~現在)

  •  
     
     

    3. 日本機械学会

  •  
     
     

    2. 日本鉄鋼協会

  •  
     
     

    1.日本塑性加工学会

▼display all

Professional Memberships

  •  
     
     

    日本金属学会

  •  
     
     

    日本機械学会

  •  
     
     

    日本鉄鋼協会

  •  
     
     

    日本塑性加工学会

  •  
     
     

    日本航空宇宙学会

  •  
     
     

    J.I.M (Japan Institute of Metal)

  •  
     
     

    J.S.M.E (Japan Society of Mechanical Engineering)

  •  
     
     

    I.S.I.J (Iron and Steel Institute of J)apan

  •  
     
     

    J.S.T.P (Japan Society for Technology of Plasticity)

  •  
     
     

    A.S.A.J (Aeronautical and Space Sciences Japan)

▼display all

Research Areas

  • Mechanics of materials and materials

Research Interests

  • 生産工学・機械材料

  • Process engineering and material engineering of mechanical parts

Awards

  • 日本塑性加工学会 論文賞

    2008  

  • Best Paper Award of J.S.T.P

    2008  

  • 日本機械学会 機械材料・材料加工部門 業績賞

    2007  

  • Mterial amd Processing Achievment Award

    2007  

  • 日本機械学会 機械材料・材料加工部門 功績賞

    2006  

  • Material and Processing Award

    2006  

  • Wire Association International 優秀講演論文賞受賞

    2005  

  • 日本機械学会フェロー

    2005  

  • Wire Association International Best Paper Award

    2005  

  • J.S.M.E Fellow

    2005  

  • Wire Association International 優秀講演論文賞受賞

    2004  

  • Wire Association International Best Paper Award

    2004  

  • 日本塑性加工学会フェロー

    2003  

  • Wire Association International優秀講演論文賞受賞

    2003  

  • J.S.T.P Fellow

    2003  

  • Wire Association International Best Paper Award

    2003  

  • 日本塑性加工学会天田賞受賞

    2000  

  • J.S.T.P Amada Memorial Award

    2000  

  • 日本鉄鋼協会共同研究賞(山岡賞)受賞

    1999  

  • I.S.I.J Ymaoka Memorial Award

    1999  

  • 日本金属学会技術開発賞受賞

    1994  

  • J.I.M Technological Development Award

    1994  

  • 日本金属学会技術開発賞受賞

    1992  

  • J.I.M Technological Development Award

    1992  

  • 大河内記念技術賞受賞

    1981  

  • Ookochi Memorial Award

    1981  

  • 日本塑性加工学会会田技術賞受賞

    1978  

  • J.S.T.P Aida Memorial Award

    1978  

  • 塑性加工学会 50周年記念 功労賞

  • J.S.T.P Memorial Award

▼display all

 

Books and Other Publications

  • 基礎機械材料

    培風館  2005

  • 日本鉄鋼協会:鉄鋼便覧

    日本鉄鋼協会  2002

  • 最新塑性加工要覧

    コロナ社  2000

  • 図解金属材料技術用語辞典

    日刊工業新聞社  1999

Research Projects

  • 機械部材の創形・創質

    受託研究

    Project Year :

    1996
    -
    2014
     

  • Material and Processing Technology

    Funded Research

    Project Year :

    1996
    -
    2014
     

  • チタン合金によるめがねフレーム成形プロセスの解明と精度向上

    共同研究

    Project Year :

    2011
    -
     
     

  • 高張力鋼線の引抜きプロセスにおける加工熱温度解析と材料特性の究明

    国際共同研究

    Project Year :

    2011
    -
     
     

  • ノースリップ型細線用伸線法の解明と伸線材特性の究明

    受託研究

    Project Year :

    2011
    -
     
     

  • Ti箔を挿入したマグネシウム合金のMg-Alクラッド板の圧延製造技術と材料特性の解明

    共同研究

    Project Year :

    2009
    -
    2011
     

  • Manufacture of Mg/Al Clad Sheet with Pure Titanium Foil Inserts by Roll-bonding

    Cooperative Research

    Project Year :

    2009
    -
    2011
     

  • マグネシウムの成形加工技術

    共同研究

    Project Year :

    2000
    -
    2011
     

  • Metal Forming Behavior of AZ61 Magnesium Alloy

    Cooperative Research

    Project Year :

    2000
    -
    2011
     

  • 棒線材におけるローラーレベラー矯正の実験的・理論的検討

    受託研究

    Project Year :

    1998
    -
    2011
     

  • Experimental and Numerical Analysis of Roller Leveler Straightening for Coiled Bar and Wire

    Funded Research

    Project Year :

    1998
    -
    2011
     

  • ピストンリングにおける曲げプロセスの究明

    受託研究

    Project Year :

    2010
    -
     
     

  • 棒線材のねじり付加せん断加工

    共同研究

    Project Year :

    2010
    -
     
     

  • Improoving of Cutting of Bars and Wire with Static Shear Load and Torsion

    Cooperative Research

    Project Year :

    2010
    -
     
     

  • 高張力鋼板の伸びフランジにおける成形性

    受託研究

    Project Year :

    2007
    -
    2010
     

  • Mechanism of Deformation Process and Blank Shape of Stretch Flanging Fracture of High-Tensile-Strength Steel

    Funded Research

    Project Year :

    2007
    -
    2010
     

  • ダイス伸線における線径変化の解析的検討

    受託研究

    Project Year :

    2009
    -
     
     

  • 極細線のブレード矯正と温間矯正による高真直化の実験的・解析的

    受託研究

    Project Year :

    2009
    -
     
     

  • Theoretical Analysis of High Dimensional Accuracy by Drawing

    Funded Research

    Project Year :

    2009
    -
     
     

  • Rotational Blade Straightening and Warm Straightening for Wire with Experimental and Numerikal FEM Analysis),

    Funded Research

    Project Year :

    2009
    -
     
     

  • 航空機用FSW(摩擦撹拌接合)における接合部の強度特性

    共同研究

    Project Year :

    2007
    -
     
     

  • 航空機用強度部材のショットピーニングによる疲労強度向上

    共同研究

    Project Year :

    2007
    -
     
     

  • Strength Propaerty of Friction Stir Welded Aluminum Alloy for Air Craft

    Cooperative Research

    Project Year :

    2007
    -
     
     

  • Inprooving of Fatigue Strength of Air Craft by Shot Peening

    Cooperative Research

    Project Year :

    2007
    -
     
     

  • CO2レーザを用いた ポリエチレンフィルムの切断加工

    受託研究

    Project Year :

    2005
    -
    2007
     

  • ひずみ誘起変態を利用したマイクロ磁気スケール

    受託研究

    Project Year :

    2003
    -
    2006
     

  • Development of Micro Scale Rod by using Strain Induced Transformation Roller Leveler Straightening for Bar in Coil

    Funded Research

    Project Year :

    2003
    -
    2006
     

  • 硬さによる機械的特性の究明

    受託研究

    Project Year :

    2002
    -
    2005
     

  • Relation between Mechanical Properties and Results of Hardness Test

    Funded Research

    Project Year :

    2002
    -
    2005
     

  • ローラーダイス伸線における倒れの検討

    受託研究

    Project Year :

    2001
    -
    2005
     

  • Tilting under wire roller drawing

    Funded Research

    Project Year :

    2001
    -
    2005
     

  • チューブハイドロフォーミングの数値解析

    共同研究

    Project Year :

    2000
    -
    2005
     

  • Nyumerical Analysis of Tube Hydroforming

    Cooperative Research

    Project Year :

    2000
    -
    2005
     

  • 段付きダイスによる鋼線の超平滑化引抜き

    受託研究

    Project Year :

    1999
    -
    2005
     

  • Ultra-Smoothing Bar and Wire by Drawing Process with Protrusion Die

    Funded Research

    Project Year :

    1999
    -
    2005
     

  • 加工誘起変態を利用した磁気目盛りの開発

    Project Year :

    1998
    -
    2005
     

  • Magnetic Scaling Rod with Transformation Induced Plasticity

    Project Year :

    1998
    -
    2005
     

  • 異形形鋼の曲げ技術

    受託研究

    Project Year :

    2000
    -
    2004
     

  • Bending Method of Deformed Products

    Funded Research

    Project Year :

    2000
    -
    2004
     

  • 棒線圧延の倒れの解析

    Project Year :

    1999
    -
    2004
     

  • Analysis of Twisting during Bar and Rod Rolling

    Project Year :

    1999
    -
    2004
     

  • 板材の対向液圧成形の弾塑性数値シミュレーション

    共同研究

    Project Year :

    2002
    -
    2003
     

  • Development of Sheet Hydroforming Simulation Program by Elastic-Plastic Finite Element Method

    Cooperative Research

    Project Year :

    2002
    -
    2003
     

  • 棒線引抜き後残留応力におよぼすダイス形状の影響

    共同研究

    Project Year :

    1997
    -
    2000
     

  • Effect of Die Geometry on Residual Stress after Bar Drawing

    Cooperative Research

    Project Year :

    1997
    -
    2000
     

  • 曲がりと直線部を含んだハット型高張力鋼板のプレス成形時のねじれ

    受託研究

    Project Year :

    1996
    -
     
     

  • Twist of High Strength Steel Sheet Channel Product Consisting of Straight Portion Combined with Curved Portion

    Funded Research

    Project Year :

    1996
    -
     
     

▼display all

Misc

  • Mechanism of Deformation Process and Blank Shape of Stretch Flanging Fracture of High-Tensile-Strength Steel

    KUROSAWA Yuichiro, IWASHITA Ushio, ISHIKURA Mitsumoto, IWAYA Jiro, YAMANO Takayuki, KIMURA Takayuki, ASAKAWA Motoo

    Journal of the JSTP   53 ( 615 ) 357 - 361  2012

     View Summary

    In this study, the stretch flanging fracture of a C-S test piece, which has a curved part (C-part) connected to a straight part (S-part) fabricated using high-tensile-strength steel sheet, is investigated. Both experimental and FEM analyses show several strain concentrations on the edge of the flange, and deformations due to such concentrations can be explained by the consecutive occurrence of the braking effect of the stress gradient. The first concentration of strain, which triggers several strain concentrations, is induced by a nonuniform stress. The cause of the nonuniform stress is considered to be the variation in flanging-up angle during the stamping process. To verify this, a C-S test piece with an additional part (obtained by adjusting the edge contours of the curved part) is also investigated. We concluded that pieces having an additional linear and a serrated edge located outside the additional part are optimal for high formability.

    DOI CiNii

  • Ultrasmooth Bar and Wire Formed by Drawing with Protrusion Die

    KAJINO Satoshi, HATAKEYAMA Tomohiro, TAMURA Youko, OHSAWA Yuki, SHIMIZU Satoru, MURAOKA Taro, ASAKAWA Motoo

      52 ( 602 ) 370 - 374  2011

    DOI CiNii

  • Theoretical and Experimental Analyses of Diameter Variation in Cold Wire Drawing

    SHIRASAKI Sonomi, KUBOTA Hiroaki, KOMAMI Ryosuke, ASAKAWA Motoo

      52 ( 602 ) 375 - 379  2011

    DOI CiNii

  • 高張力鋼板の曲げ加工に関する弾塑性解析

    浅川基男

    塑性と加工 (J.S.T.P )   52 ( 608 ) 787 - 792  2011

    DOI

  • 平成23年度塑性加工春季講演会を振り返って

    浅川基男

    塑性と加工 (J.S.T.P )   52 ( 568 ) 993 - 994  2011

  • Roller Leveler Straightening and Additional Twisting for Coiled Wire

    Nishimura, K, Asakawa, M, Li, B

    10thICTP 2011. Steel Research Int. 2011, special edition    2011

  • Reduction of Shear Droop by Torsion with Static Shear Load of Bars and Wire

    Kajino, T, Tanaka, T, Asakawa, M

    10th ICTP 2011, Steel Research Int. 2011, special edition     592 - 597  2011

  • Effect of deformation heating produced during cold drawing on drawn bar diameter by numerical FEM analysis

    Shirakawa, T, Asakawa, 2 M, Shirasaki, S, Ohno, Y

    10th ICTP 2011, Steel Research Int. 2011, special edition     291 - 296  2011

  • Reduction of Shear Droop by Torsion with Static Shear Load of Bars and Wire

    Kajino, T, Tanaka, T, Asakawa, M

    10th ICTP 2011, Steel Research Int. 2011, special edition     592 - 597  2011

  • Roller Leveler Straightening and Additional Twisting for Coiled Wire

    Nishimura, K, Asakawa, M, Li, B

    10thICTP 2011. Steel Research Int. 2011, special edition    2011

  • Reduction of Shear Droop by Torsion with Static Shear Load of Bars and Wire

    Kajino, T, Tanaka, T, Asakawa, M

    10th ICTP 2011, Steel Research Int. 2011, special edition     592 - 597  2011

  • Effect of deformation heating produced during cold drawing on drawn bar diameter by numerical FEM analysis

    Shirakawa, T, Asakawa, 2 M, Shirasaki, S, Ohno, Y

    10th ICTP 2011, Steel Research Int. 2011, special edition     291 - 296  2011

  • Reduction of Shear Droop by Torsion with Static Shear Load of Bars and Wire

    Kajino, T, Tanaka, T, Asakawa, M

    10th ICTP 2011, Steel Research Int. 2011, special edition     592 - 597  2011

  • Evaluation of crack nucleation site and mechanical properties for friction stir welded butt joint in 2024-T3 aluminum alloy

    Takao Okada, Masako Suzuki, Haruka Miyake, Toshiya Nakamura, Shigeru Machida, Motoo Asakawa

    INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY   50 ( 1-4 ) 127 - 135  2010.09

     View Summary

    In this paper, metallographic observations, hardness measurement, and static and fatigue tests were conducted to investigate the discontinuity states which become crack nucleation sites in friction stir welded butt joints in 2-mm-thick 2024-T3 aluminum alloy and static and fatigue properties of the joint. Because different types of surface finish can be used depending on the application of the joint, several types of surface conditions were tested to evaluate their effect on crack nucleation sites and static and fatigue life. Indentation hardness tests revealed that typical hardness reduction is not necessarily observed on the section of the welding line. Based on fatigue test results, it was confirmed that there are several types of crack nucleation sites for friction stir welding (FSW) joints depending on the surface finish, and the features of the fracture surface also differ depending on the site. Furthermore, the type of discontinuity state affects the fatigue life of the FSW joint.

    DOI

  • Evaluation of crack nucleation site and mechanical properties for friction stir welded butt joint in 2024-T3 aluminum alloy

    Takao Okada, Masako Suzuki, Haruka Miyake, Toshiya Nakamura, Shigeru Machida, Motoo Asakawa

    INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY   50 ( 1-4 ) 127 - 135  2010.09

     View Summary

    In this paper, metallographic observations, hardness measurement, and static and fatigue tests were conducted to investigate the discontinuity states which become crack nucleation sites in friction stir welded butt joints in 2-mm-thick 2024-T3 aluminum alloy and static and fatigue properties of the joint. Because different types of surface finish can be used depending on the application of the joint, several types of surface conditions were tested to evaluate their effect on crack nucleation sites and static and fatigue life. Indentation hardness tests revealed that typical hardness reduction is not necessarily observed on the section of the welding line. Based on fatigue test results, it was confirmed that there are several types of crack nucleation sites for friction stir welding (FSW) joints depending on the surface finish, and the features of the fracture surface also differ depending on the site. Furthermore, the type of discontinuity state affects the fatigue life of the FSW joint.

    DOI

  • INVESTIGATION OF TWIST IN CURVED HAT CHANNEL PRODUCTS BY ELASTIC-PLASTIC FINITE ELEMENT ANALYSIS

    M. Takamura, M. Sakata, A. Fukui, T. Hama, Y. Miyoshi, H. Sunaga, A. Makinouchi, M. Asakawa

    INTERNATIONAL JOURNAL OF MATERIAL FORMING   3   131 - 134  2010.04

     View Summary

    This study concerns twist phenomena occurring in curved hat channel products and aims to clarify the causes of twist using physical quantities obtained by finite element analysis. Several drawing heights were examined. We evaluated the torque around the longitudinal axis, which can be regarded as the driving force of the twist. In addition, transitions of the torque during the process of tool removal were analyzed. After removing the die and blank holder, the twist torque in models with larger drawing heights became negative, accounting for the positive twist, which occurs after punch and pad removal. On the other hand, the twist torque in models with smaller drawing heights remained positive, accounting for the negative twist. Such analyses of the transition of twist torque provide useful information when considering measures for reducing twist.

    DOI

  • INVESTIGATION OF TWIST IN CURVED HAT CHANNEL PRODUCTS BY ELASTIC-PLASTIC FINITE ELEMENT ANALYSIS

    M. Takamura, M. Sakata, A. Fukui, T. Hama, Y. Miyoshi, H. Sunaga, A. Makinouchi, M. Asakawa

    INTERNATIONAL JOURNAL OF MATERIAL FORMING   3   131 - 134  2010.04

     View Summary

    This study concerns twist phenomena occurring in curved hat channel products and aims to clarify the causes of twist using physical quantities obtained by finite element analysis. Several drawing heights were examined. We evaluated the torque around the longitudinal axis, which can be regarded as the driving force of the twist. In addition, transitions of the torque during the process of tool removal were analyzed. After removing the die and blank holder, the twist torque in models with larger drawing heights became negative, accounting for the positive twist, which occurs after punch and pad removal. On the other hand, the twist torque in models with smaller drawing heights remained positive, accounting for the negative twist. Such analyses of the transition of twist torque provide useful information when considering measures for reducing twist.

    DOI

  • 浅川研究室には夏休みがない?

    浅川基男

    ふぇらむ(Ferum)   15 ( 9 ) 567 - 574  2010

  • 指導者の影響力

    浅川基男

    KYB技法   41   1  2010

  • Improvement of Straightness in Tension Annealing for Superfine Wire

    Urabe, M, Asakawa, M, Kajino, S, Hamada, R, Kashiyama, D

       2009

  • 大学は基礎教育に徹せよ

    塑性と加工   46 ( 536 ) 1 - 2  2009

  • コイル状線材の回転現象とローラーレベラー矯正

    浅川基男

    線材とその製品   47 ( 4 ) 10 - 11  2009

    CiNii

  • 棒線材におけるローラレベラーによるコイル材の高真直化の実験的・解析的検討

    濱田亮太, 浅川基男, 入沢辰之介, 相澤重之, 永平めぐみ, 甘利正彦

    鉄と鋼 (Tetu-to-Hagane)   95 ( 11 ) 780 - 787  2009

    DOI CiNii

  • 回転矯正および温間引張り矯正を用いた極細線の高真直化

    占部元彦, 浅川基男, 梶野智史, 吉田将大

    鉄と鋼 (Tetu-to-Hagane)   95 ( 11 ) 794 - 800  2009

    DOI CiNii

  • AZ61マグネシウム合金板の繰返し曲げ加工に伴う双晶形成が集合組織に及ぼす影響と成形性向上

    須長好古, 田中良典, 浅川基男, 加藤正仁, 小林勝

    軽金属   59 ( 12 ) 655 - 658  2009

    DOI CiNii

  • Improvement of Straightness in Tensino Annealing for Superfine Wire

    Urabe, M, Asakawa, M, Kajino, S, Yoshida, M, Hamada, R, Kashiyama, D

    Wire J. Int.     66 - 71  2009

  • Effect of mechanical properties on diameter of drawn bars

    TANAKA Y.

    Wire J. Int.   42 ( 11 ) 66 - 71  2009

    CiNii

  • Improvement of Straightness in Tension Annealing for Superfine Wire

    Urabe, M, Asakawa, M, Kajino, S, Hamada, R, Kashiyama, D

       2009

  • Improvement of Straightness in Tensino Annealing for Superfine Wire

    Urabe, M, Asakawa, M, Kajino, S, Yoshida, M, Hamada, R, Kashiyama, D

    Wire J. Int.     66 - 71  2009

  • Effect of Mechanical Properties on Diameter of Drawn Bars

    Tanaka, Y., M, Asakawa, R, Komami, H, Kubota, H

    Wire J. Int.     66 - 71  2009

  • Effect of Additional Shear Strain Layer on Mechanical Properties of Fine Drawn Wire

    Wire J. Int.     58 - 63  2008

  • 圧延・引抜き

    浅川基男

    特殊鋼   57   58 - 63  2008

  • 有限要素法を用いた伸線・引抜き・矯正技術の動向

    浅川基男

    線材とその製品   46   6 - 12  2008

  • Effect of Mechanical Properties on Diameter of Drawn Steel Materials

    Tanaka, Y, Asakawa, M, Komami, R, Kubota, H

    Wire J. Int.    2008

  • Effect of die semi-angle and multi-pass drawing on additional shear strain layer

    HOSODA K.

    Wire J. Int.   41 ( 11 ) 68 - 73  2008

    CiNii

  • Improvement of straightness in coiled bar with roller leveler straightener

    HAMADA R.

    Wire J. Int.   41 ( 9 ) 81 - 87  2008

    CiNii

  • 有限要素法を用いた伸線・引抜き・矯正技術の動向

    浅川基男

    線材とその製品     6 - 11  2008

  • Relationship between Microstructure of Additional Shear Strain Layer and Increase in Tensile Strength of Finely Drawn Wire : Additional Shear Strain Layer at Surface of Drawn Wire II

    KAJINO Satoshi, ASAKAWA Motoo

    Journal of the JSTP   49 ( 568 ) 409 - 413  2008

     View Summary

    Fine wires (with a diameter less than 0.4 mm) have been extensively used for precision machines and other devices. It is well known that finely drawn wires have a much higher tensile strength than thick drawn wires. In the drawing process, a large shear deformation zone with a hardened layer, known as the "additional shear strain layer", is generated beneath the surface layer of the wire. It was clarified that the depth of this additional shear strain layer was about 0.04 mm for wires of various diameters. As the diameter becomes small, the area ratio of the additional shear layer increases. Hence, the additional shear strain layer is a factor contributing to the high tensile strength of fine wires. In this paper, the main purpose is to discuss the cause of the increase in the tensile strength of the additional shear strain layer metallurgically. Thus, the crystal orientation and microstructure was measured by the Electron Back-Scatter Diffraction (EBSD) method. It was ascertained that the crystal of the surface layer was subdivided more finely than the center, and then the tensile strength of the surface layer increased.

    DOI CiNii

  • Effect of Drawing Condition and Multipass Drawing on Additional Shear Strain Layer of Finely Drawn Wire : Additional Shear Strain Layer at Surface of Drawn Wire III

    KAJINO Satoshi, ASAKAWA Motoo, HOSODA Kazuki, MAEDA Yasuhiro

    Journal of the JSTP   49 ( 568 ) 414 - 418  2008

     View Summary

    Fine wires (with a diameter less than 0.4 mm) have been extensively used for precision machines and other devices. It is well known that finely drawn wires have a much higher tensile strength than thick drawn wires. One of the main factors for this characteristic has been determined to be an "additional shear strain layer". The main purpose of this research is to clarify the relationship between the additional shear strain layer and the tensile strength of fine wire. In this paper, firstly the effects of the friction between the die and the wire and the die semiangle on the additional shear strain layer were investigated. It was ascertained that friction work was most effective for increasing the tensile strength of the additional shear strain layer and increasing in the tensile strength of the fine wire. Secondly, the additional shear strain layer generated in the multipass drawing was investigated. In the case of low-carbon steel, the increase in tensile strength of the additional shear strain layer was limited. On the other hand, the tensile strength of the additional shear strain continued to increase in high-carbon steel.

    DOI CiNii

  • 難燃性マグネシウム合金多方向鍛造・圧延による結晶粒微細化と2次成形性向上

    軽金属   58 ( 9 ) 462 - 463  2008

    DOI

  • 繰り返し曲げ加工による双晶形成がAZ61マグネシウム合金板の集合組織に及ぼす影響

    田中良典, 浅川基男, 加藤正仁, 小林勝

    軽金属   58 ( 10 ) 522 - 523  2008

    DOI CiNii

  • Effect of Additional Shear Strain Layer on Mechanical Properties of Fine Drawn Wire

    Wire J. Int.     58 - 63  2008

  • Effect of Mechanical Properties on Diameter of Drawn Steel Materials

    Tanaka, Y, Asakawa, M, Komami, R, Kubota, H

    Wire J. Int.    2008

  • Effect of Die Semi-angle and Multi-pass Drawing on Additional Shear Strain Layer

    Hosoda, K, Asakawa, M, Kajino, S, Maeda, Y

    Wire J. Int.     68 - 73  2008

  • Improvement of Straightness Coiled Bar with Roller Leveler Straightener

    Hamada, R, Asakawa, M, Nagahira, M, Amari, M

        81 - 87  2008

  • Effect of Thermal Expansion of Die on Accuracy of Drawn Bars and Wires

    Komami, R.. Kajino, S, Asakawa, M, Kubota, H

    Wire J. Int.    2007

  • Basic study of straightness in roller leveler straightening for Bar in coil

    NAGAHIRA M.

    Wire J. Int.   40 ( 11 ) 76 - 79  2007

    CiNii

  • Effect ob Back-Tension in Drawing on Diameter ob Bar and Wire

    Kubota, H, Asakawa, M, Kajino, S

    Wire J. Int.     75 - 79  2007

  • Effect of Thermal Expansion of Die on Accuracy of Drawn Bars and Wires

    Komami, R.. Kajino, S, Asakawa, M, Kubota, H

    Wire J. Int.    2007

  • Basic Study of Straightness in Roller Leveler Straightening for Bar in Coil

    Nagahira, M, Asakawa, M, Aizawa, S, Motoda, M, Yoshida. H, Amari, M

    Wire J. Int.,     76 - 79  2007

  • Effect ob Back-Tension in Drawing on Diameter ob Bar and Wire

    Kubota, H, Asakawa, M, Kajino, S

    Wire J. Int.     75 - 79  2007

  • Effect of "additional shear strain layer" on tensile strength and microstructure of fine drawn wire

    S. Kajino, M. Asakawa

    Journal of Materials Processing Technology   177 ( 1-3 ) 704 - 708  2006.07

     View Summary

    Fine wires of the order of 0.1 mm in diameter have become popular for mechanical and electrical applications. In the drawing process, a large shear deformation zone with a hardened layer, referred to as the "additional shear strain layer", is generated beneath the surface layer of the wire. This study clarified that the depth of this additional shear strain layer was about 0.04 mm for various diameter fine wires. As the diameter decreases, the area ratio of additional shear layer increases. Hence, the additional shear strain layer is a factor for the improvement in high strength and ductility of the wires. In order to discuss the cause of the increase in the surface layer's tensile strength, the crystal orientation was measured via the electron back-scatter diffraction (EBSD) method. It was ascertained that the crystal of surface layer was subdivided more easily than the center layer, and therefore the tensile strength of surface layer increased. © 2006 Elsevier B.V. All rights reserved.

    DOI CiNii

  • Effect of "additional shear strain layer" on tensile strength and microstructure of fine drawn wire

    S. Kajino, A. Asakawa

    JOURNAL OF MATERIALS PROCESSING TECHNOLOGY   177 ( 1-3 ) 704 - 708  2006.07

     View Summary

    Fine wires of the order of 0.1 mm in diameter have become popular for mechanical and electrical applications. In the drawing process, a large shear deformation zone with a hardened layer, referred to as the "additional shear strain layer", is generated beneath the surface layer of the wire. This study clarified that the depth of this additional shear strain layer was about 0.04 mm for various diameter fine wires. As the diameter decreases, the area ratio of additional shear layer increases. Hence, the additional shear strain layer is a factor for the improvement in high strength and ductility of the wires.
    In order to discuss the cause of the increase in the surface layer's tensile strength, the crystal orientation was measured via the electron back-scatter diffraction (EBSD) method. It was ascertained that the crystal of surface layer was subdivided more easily than the center layer, and therefore the tensile strength of surface layer increased. (c) 2006 Elsevier B.V All rights reserved.

    DOI CiNii

  • Finite element analysis of tilting of metal in bar rolled with three-roll mill

    M Asakawa, K Kobayashi, Y Katayama, D Shioga, J Yanagimoto

    ISIJ INTERNATIONAL   46 ( 4 ) 553 - 559  2006

     View Summary

    Boiled metal bars and rods often exhibit tilting, which is rotation of the material around the pass line under rolling. Tilting may result in a defective shape. High dimensional accuracy is demanded in 3-roll rolling because 3-roll rolling is used for finishing passes. Therefore, the design of calibers and a rolling sequence that can reduce tilting is important from industrial aspects. In this study, three-dimensional FE analysis is applied to the prediction of metal tilting under 3-roll rolling in an oval-round pass and a hexagon-oval pass. The difference in the characteristics of tilting according to the contact contour between metal and the roll is investigated by classifying the characteristics of tilting into two modes, with the aim of clarifying the threshold for the occurrence of overturning and restoration resulting from tilting. Predicted results agree well with the experimental measurements of tilting, and the validity of method for analyzing tilting is confirmed. Moreover, it is found that the mechanism of tilting differs according to the contact contour. In an oval-round pass that is of a convex contact type, the bar tilt angle is difficult to decrease once tilting has occurred. In a hexagon-oval pass that is of a concave contact type, although the bar tilt angle tends to increase when the entrance cross section is constrained strongly, the bar tilt angle tends to decrease after constraint becomes relatively small.

    DOI CiNii

  • Effect of Additional Shear Strain Layer on Tensile Strength and Ductility of Finely Drawn Wire : Additional Shear Strain Layer at Surface of Drawn Wire I

    KAJINO Satoshi, ASAKAWA Motoo

    Journal of the Japan Society for Technology of Plasticity   47 ( 549 ) 953 - 957  2006

     View Summary

    Fine wires approximately on the order of 0.1 mm in diameter have become popular for mechanical and electrical applications. In general, it is well known that finely drawn wires have high strength while maintaining ductility. It has been determined that a hardened layer of approximately 0.04 mm depth, referred to as the "additional shear strain layer," is generated beneath the surface layer of fine wires during drawing. By performing tensile tests on fine wires, with and without the additional shear strain layer, the effect of this layer on the strength and ductility of fine wires was investigated. The tensile strength decreased as the surface layer was removed in all the wires. The additional shear strain layer affected the tensile strength of the fine wires markedly.

    DOI CiNii

  • Effect of additional shear strain layer on tensile strength and ductility of fine drawn wire

    KAJINO S.

    Wire J. Int.   39 ( 9 ) 64 - 68  2006

    CiNii

  • Effect of Additional Shear Strain Layer on Mechanical Properties of Fine Drawn Wire

    Kajino, S, Asakawa

    Wire J. Int.     95 - 111  2006

  • Basic Study of Straightness in Roller Leveler Straightening for Bar in Coil

    Nagahira, M, Asakawa, M, Aizawa, S, Motoda, M, Yoshida, H, Amari, M

    Wire J. Int.,     124 - 131  2006

  • Experimental and Theoretical Analyses of Tilting in Roller Die Drawing

    Shigeta, H, Asakawa, M, Shimizu, A, Yanagimoto J

    Wire J. Int     132 - 144  2006

  • Finite element analysis of tilting of metal in bar rolled with three-roll mill

    M Asakawa, K Kobayashi, Y Katayama, D Shioga, J Yanagimoto

    ISIJ INTERNATIONAL   46 ( 4 ) 553 - 559  2006

     View Summary

    Boiled metal bars and rods often exhibit tilting, which is rotation of the material around the pass line under rolling. Tilting may result in a defective shape. High dimensional accuracy is demanded in 3-roll rolling because 3-roll rolling is used for finishing passes. Therefore, the design of calibers and a rolling sequence that can reduce tilting is important from industrial aspects. In this study, three-dimensional FE analysis is applied to the prediction of metal tilting under 3-roll rolling in an oval-round pass and a hexagon-oval pass. The difference in the characteristics of tilting according to the contact contour between metal and the roll is investigated by classifying the characteristics of tilting into two modes, with the aim of clarifying the threshold for the occurrence of overturning and restoration resulting from tilting. Predicted results agree well with the experimental measurements of tilting, and the validity of method for analyzing tilting is confirmed. Moreover, it is found that the mechanism of tilting differs according to the contact contour. In an oval-round pass that is of a convex contact type, the bar tilt angle is difficult to decrease once tilting has occurred. In a hexagon-oval pass that is of a concave contact type, although the bar tilt angle tends to increase when the entrance cross section is constrained strongly, the bar tilt angle tends to decrease after constraint becomes relatively small.

    DOI CiNii

  • Effect of Additional Shear Strain Layer on Tensile Strength and Ductility of Fine Drawn Wire

    Kajino, S Asakawa

    Wire J. Int.     64 - 68  2006

  • Effect of Additional Shear Strain Layer on Mechanical Properties of Fine Drawn Wire

    Kajino, S, Asakawa

    Wire J. Int.     95 - 111  2006

  • Basic Study of Straightness in Roller Leveler Straightening for Bar in Coil

    Nagahira, M, Asakawa, M, Aizawa, S, Motoda, M, Yoshida, H, Amari, M

    Wire J. Int.,     124 - 131  2006

  • Experimental and Theoretical Analyses of Tilting in Roller Die Drawing

    Shigeta, H, Asakawa, M, Shimizu, A, Yanagimoto J

    Wire J. Int     132 - 144  2006

  • 2ロール矯正における曲げの塑性率と繰り返し回数が真直性に与える影響-棒線における矯正と残留応力の研究 第3報-

    柳橋卓, 浜孝之, 小野田雄介, 浅川基男

    塑性と加工   46 ( 537 ) 50 - 54  2005

  • Generating a mechanism of delamination in high carbon steel wire by experimental

    SUZUKI Y.

    Wire J. Int.   38 ( 10 ) 70 - 72  2005

    CiNii

  • Investigation of factors which cause breakage occurring on a hydroformed automotive part

    Hama, T, Asakawa, M, Makinouchi, A

    Journal of Materials Processing Technology   ( 150 ) 10 - 17  2004

    DOI

  • Simulation of Hammering by Static Explicit FEM

    Hama, T, Asakawa, M, Fukiharu.H, Makinouchi, A

    ISIJ Int.   44 ( 1 ) 123 - 128  2004

    DOI CiNii

  • Producing bar and wire with ultra-smoothing and lower residual stress by new drawing

    ASAKAWA M.

    Wire J. Int.   44 ( 4 ) 144 - 151  2004

    CiNii

  • Warm precision forging and upsetting for the extruded billet of AZ61 Magnesium alloy

    Doseok Lee, Motoo Asakawa, Yohei Tanno, Masaru Kobayashi, Kanichi Hatsukano, Kunio Matsuzaki

    STEEL GRIPS 2 (Metal forming 2004)     621 - 626  2004

  • Effect of Additional Shear Strain Layer on Mechanical Properties of Fine Drawn Wire

    S.Kajino, M.Asakawa, W.Z.Misiolec, A.R.Bandar

    STEEL GRIPS 2 (Metal forming 2004)    2004

  • Study on Warm Caliber Rolling of AZ31 Magnesium Alloy

    Yohei Tanno, Takaki Mukai, Motoo Asakawa, Masaru Kobayashi

    Materials Science Forum   419 ( 422 ) 359 - 364  2003

  • Twist Resulting in High Strength Steel Sheet Channel Product Consisting of Straight Portion Combined with Curved Portion

    Iyama.T, Hoshi.T, Odanaka.K, Fujishiro.Y, Asakawa.M, Hayashi.I

    JSME International Journal A   46 ( 3 ) 419 - 425  2003

    DOI CiNii

  • Ultra-Smoothing Bar and Wire by Drawing Process with Protrusion Die

    Asakawa.M, Kajino.S, Ohsawa.Y, Hashimoto.S

    Wire J. Int.     111 - 115  2003

  • Analysis of Hydrostatic Tube Bulging with Cylindrical Die Using Static Explicit FEM

    Hama, T, Asakawa, M, Fuchizawa, S, Makinouchi, A

    Materials Transactions   44   945 - 955  2003

    DOI

  • ダオヤ-スクウェア圧延・スクウェア-オーバル圧延時の被圧延材の倒れの実験的・理論的研究

    浅川基男, 宮澤英之, 戸井真, 片山勇輝

    鉄と鋼   89  2003

    DOI

  • 各種製品寸法・材料強度に対応した金型設計法-高張力鋼板を用いた箱形断面成形の研究 第2報-

    浅川基男, 桑山勲, 浜孝之, 細田寛之, 藤城良夫, 林郁彦

    塑性と加工   43 ( 52 ) 71 - 75  2002

  • 線材とその2次加工における創形・創質

    CAMP-ISIJ   11;(264)  1998

  • 棒鋼線材における矯正加工の動向

    第84回中小形部会/日本鉄鋼協会    1998

  • 棒鋼・線材の引抜き条件と残留応力の解析

    塑性と加工/日本塑性加工学会   38;433  1997

  • ロール伸線はどこまで進歩したか

    塑性と加工/日本塑性加工学会   38;440(13)  1997

  • New Tribo-Test for Cold Forging Processes by Localizing Rod-Drawing Method

    Advanced Technology of Plasticity/International Conference on Technology of Plasticity   5th ICTP, vol.1  1996

  • 棒・線技術者の大学転身にあたって

    第42回伸線技術分科会/日本塑性加工学会    1996

  • 線材圧延技術(特別講演)

    第81回線材部会/日本鉄鋼協会    1996

  • 棒鋼圧延技術(特別講演)

    第81回中小形部会/日本鉄鋼協会    1996

  • New Tribo-Test for Cold Forging Processes by Localizing Rod-Drawing Method

    Advanced Technology of Plasticity/International Conference on Technology of Plasticity   5th ICTP;1  1996

  • レーザ加熱・急速冷却による局部変態組織を利用した精密磁気スケール

    熱処理/熱処理技術協会   36;5  1996

  • 特集:表面改質にレーザを使おう

    日経メカニマル/日経BP社   468  1995

  • Development of Magnetic Scaling Rods with T.R.I.P and Laser Beam Technology for Mechanical and Electrical Use.

    Tsukamoto Takashi, Asakawa Motoh, Sudoo Chuzo, Kouso Masashi, Nakasato Masakazu

    Bulletin of the Japan Institute of Metals   33;4 ( 4 ) 435 - 437  1994

    DOI CiNii

  • 高炭素鋼線の強度と伸線加工性

    住友金属(技報)/住友金属工業   45;4  1993

  • 高張力細線の高真直化と3次元曲がりの形状評価

    住友金属(技報)/住友金属工業   45;4  1993

  • Development of Magnetic Scaling Rod with Laser Beam

    Wire Journal International/International Wire Association   1992.9.1  1992

  • 有限要素法を用いた伸線・引抜き・矯正技術の動向

    浅川基男

    特殊鋼  

▼display all

Industrial Property Rights

  • 段付きダイス組立体

    Patent

     View Summary

    特開2004- 9112

  • 磁気スケールの製造方法

    Patent

     View Summary

    特開2001-027550

 

Overseas Activities

  • 欧米における機械材料・加工学の研究と教育

    2002.04
    -
    2002.09

    ドイツ   アーヘン工科大学

    アメリカ  

Internal Special Research Projects

  • AZ61マグネシウム合金における集合組織制御圧延技術の開発

    2007  

     View Summary

    特定課題研究費終了報告「AZ61マグネシウム合金における組織制御圧延技術の開発」本研究では,AZ61マグネシウム合金圧延板に曲げ加工を施すことによる双晶変形の導入が底面集合組織の分散に及ぼす影響に着目した.圧延板の底面集合組織の制御と曲げ成形性向上に関する新たな知見を得て,今後の使用拡大への貢献に寄与することを目的とする. 曲げ加工によるMg合金板の双晶形成を利用した集合組織分散についての研究例は極めて少ない.本研究では,圧延板に繰り返し曲げ加工を施すことで,引張り・圧縮ひずみを交互に繰り返し付与し,底面集合組織を分散させることを試みた.加工温度は,十分な転位を導入でき結晶粒微細化も期待できる冷間とし,板表面に3 %のひずみを付与できるパンチを用いて繰り返し曲げ加工を施した.その後,性質分析としてSEM-EBSPを用いて双晶形成に伴う集合組織変化を解析し,また,成形性評価には,実部材への適用範囲が広いV曲げ成形性試験を用いた.その結果,AZ61マグネシウム合金圧延板において曲げ加工による,底面集合組織変化と曲げ成形性に関して以下の知見が得られた.(1)曲げ加工をすると曲げ圧縮側に引張り双晶が形成し,繰り返し曲げ加工を施すことで底面集合組織が分散する.(2)繰り返し曲げ加工を施す事で,従来のMg圧延板において困難であった冷間曲げ加工が,R/t=3(R:パンチ半径,t:板厚)で割れ・不良現象が発生することなくV曲げ成形可能となり,成形性の良好な圧延板が作製できる.(3)繰り返し曲げ後の圧延板は,473 KにおいてR/t=1の厳しい条件で成形可能であった.繰り返し曲げ加工を施す事で底面集合組織が分散化し,成形性の良好な圧延板が得られた.

  • 極細線をベースとしたマイクロ加工

    2003  

     View Summary

    細線材に要求される技術課題は,細径化,高強度化,高延性化などであり,特に高強度化に関する研究が最も注目を集めている.高強度化の重要な問題点として,最終到達強度に対する線径の影響すなわち「寸法効果」が挙げられる.この寸法効果を解明することは,細線材の高強度化技術の前進に必須である.伸線加工では,ダイスと線材間の摩擦により,付加的せん断ひずみ層が発生する.また,付加的せん断ひずみ層は線径によらず一定の深さであることが確認された.本研究では,この付加的せん断ひずみ層が細線の引張り強さ向上に寄与していると考え,その詳細を力学的,結晶組織学的に究明した.低炭素鋼SWRM6の線材を対象にして,EBSDを用いた結晶方位測定から集合組織によって表層部と中心部の結晶回転を検討した.また,せん断ひずみ層の引張り強さ上昇の要因として結晶粒分断化に焦点をあて,結晶方位差を観察した結果,以下の知見を得た.(1)付加的せん断ひずみ層のある表層部の集合組織には結晶方位が2つ存在している.一方中心部と同じ方位,もう一方は付加的せん断変形による結晶格子の回転で発生した方位と推定される.(2)伸線後の結晶粒は,15deg以下の結晶方位差で分断化されていることが観察された.また,中心部と表層部を比較した場合,表層部の結晶粒がより細かく分断化されていることが確認された.これは表層部のみで発生する結晶回転に起因すると考えられる.(3)低炭素鋼の多パス伸線材において,真ひずみe = 0.3までは付加的せん断ひずみ層の引張り強さが増加した.しかし,それ以上のひずみでは,付加的せん断ひずみ層と中心部の引張り強さ差が一定となることが観察された.これは,表層部と中心部の結晶粒数の比率が一定の値になるためであると考えられる.

  • オーステナイト鋼の加工誘起変態を活用した磁気記録材の創質・創形

    2000  

     View Summary

     精密機械、産業用ロボット、自動車、鉄道車両、建設機械等では、空圧や油圧を利用した位置検出用アクチュエータが多く採用されている。従来のピストンロッドの位置検出法としては、ロータリーエンコーダ等をシリンダ外部に装着する方法や、ロッドに等間隔の溝を設け、銅等の磁性の異なる金属でその溝を埋め磁性部と非磁性部を交互に配列し、磁気センサで検知する方法が実用化されている。しかし、いずれの方法も検出精度や堅牢さに問題を抱えていた。そこで、この磁気特性を利用した方法として、オーステナイト鋼のひずみ誘起変態を利用した方法が実用化されている。すなわち冷間加工によりロッドをマルテンサイト化(磁性化)した後、レーザを一定間隔で加熱照射し再びオーステナイト化(非磁性化)する方法である。しかしレーザ加工は生産性が低く高価なため、特殊な用途に限られていた。そこでレーザ加工法に代わり、圧印機による塑性加工法でマルテンサイト化する磁気記録法を開発し、レーザ加工に比べ格段に生産性の高い加工法を検討した。本年度の研究では、さらに回転加工法を考案し波形の安定化を図った。また表層溶体化処理により、内部にマルテンサイトを残し、ロッドの高強度化を図った。 この結果以下の成果を得た。 回転加工の局部加工によって、圧印法に比べ安定した高出力のセンサ波形を取得することができた。磁気の波形が最も明確に検知できる加工条件は、工具頂角45°、目盛り深さ0.15mm、ピッチ2mmの場合である。内部マルテンサイトにより、ロッドの引張り強度は750MPaから1000MPaに、また耐力値は230MPaから700MPaに増加し、高強度化できた。また表層のみをオーステナイト化するための最適な高周波処理条件は、φ17ロッド使用時において、出力108kW、周波数30kHz、コイル移動速度8~14mm/secである。 以上より、塑性加工によるオーステナイト鋼のひずみ誘起変態を利用し適切な条件で回転加工を施すことにより、レーザ加工法に近い安定した波形を得ることができ、従来システムと同等の0.1mm単位の位置検出精度を実現した。また内部マルテンサイト化により、ロッドの機械的性質を改善することができ、生産性の高い塑性加工による磁気目盛りの作成が可能である。

  • オーステナイト鋼の加工誘起変態を活用した磁気記録材の基礎研究

    1998  

     View Summary

     機密機械、産業用ロボット、自動車、鉄道車両、建設機械などでは、空圧や油圧を利用した位置検出用アクチュエータが多く採用されている。従来のピストンロッドの位置検出法としては、ロータリエンコーダや作動トランス等位置測定装置をシリンダ外部に装着する方法やロッドに等間隔の溝を設け、銅等の磁性の異なる金属でその溝を埋め磁性部と非磁性部を交互に配列し、磁気センサで検知する方法があった。しかしいずれも検出精度や堅牢さに問題を抱えていた。そこで、この磁気特性を利用した方法として、オーステナイト鋼のひずみ誘起変態を利用する方法が実用化されている。マルテンサイト化した材料を一定間隔でレーザにより溶融さっせてオーステナイト組織にすることで磁気スケールを形成する。しかしレーザによる溶融は加工時間が長くかかり生産性が低く高価なため、特殊な用途に限定されていた。そこでレーザ加工法に代わり塑性加工による磁気記録法を採用することにより、より生産性の高い加工法を研究開発した。この結果以下の成果を得た。(1) 加工部分のひずみ、硬さとマルテンサイト生成率の関係を求めることができた。これにより、加工後のマルテンサイトの析出状況を把握することができ、磁気目盛りを作成する際の圧印工具最適形状を評価する指針を得ることができた。(2) 磁気の波形が明瞭に検知できる圧印形状は三角形型であり、工具頂角60°ピッチ3mmの場合に既存のレーザ加工による磁気目盛の磁気波形に近い波形を得ることができる。(3) マルテンサイトの分布状態は長手方向、深さ方向とも0.5mmに集中分布する状態を適当とする。 以上より、塑性加工によるオーステナイト鋼のひずみ誘起変態を利用し適切な条件の下で圧印すれば、従来システム同等の0.1mm単位の位置検出精度を実現、かつ生産性の高い塑性加工による磁気目盛りの作成が可能である。

  • 電子・電気機器用線材および自動専用シャフト部品の高真直化に関する基礎的研究

    1996  

     View Summary

     棒鋼・綿材の引抜きプロセスにおいて、ダイス形状、減面率、引抜き速度、摩擦係数等の加工条件は最終製品の品質特性に大きな影響を与える。特に残留応力は、引抜き後の切削・研磨等の機械加工あるいは熱処理により寸法、形状、特に真直度に大きな変化を与えることがある。また通常の引抜きでは表層に引張りの残留応力が発生しやすく、疲労強度低下の要因ともなる。したがって引抜き加工では残留応力を極力少なくすることが非常に重要である。そこで著者らは、引抜き加工時の残留応力を実験により測定するとともに、汎用弾塑性有限要素法(ABAQUS)により比較評価した。 直径18mm、S45Cの焼入、焼戻し材を引抜いて残留応力を検討した結果、下記の知見が得られた。 1)弾塑性有限要素法(ABAQUS)により実験との比較評価を行った結果、本解析が実プロセスの現象をよく再現し、残留応力の解析に有効な手段であることが判明した。 2)ダイス全角度2αを8゜~20゜に変化させ、減面率r=13.8%の一定値で引抜いた結果、2α=15゚付近で軸方向表面の残留応力のピークが出現する。すなわち工業上最も活用されているダイス角度は、残留応力の観点からは必ずしも適切な選択ではなく、残留応力軽減を第一目的とするならば、ダイス角を小さくすることが必要である。 3)ダイス角度2α=14゚の一定値とし減面率r=5~25%に変化させ引抜いた結果、r=10~15%前後で引張残留応力のピークが出現する。この付近の減面率は工業上よく使用される領域ではあるが、これを避けて、さらに増大あるいは減少させることにより引張残留応力は軽減する。以上の現象は接触長さ比L/dで整理できる。 以上の結果から、引抜き後切削加工時のシャフト部品の曲がり防止のため、ダイス角度を小さく改善した結果、曲がりが大幅に軽減し、不良品発生の防止、工程の合理化に貢献しえた。