• Search Research Projects
  • Search Researchers
  • How to Use
  1. Back to previous page

Precipitation Mechanisms of Ordered Phases in Ti-and Ni-base Alloys

Research Project

Project/Area Number 07650771
Research Category

Grant-in-Aid for Scientific Research (C)

Allocation TypeSingle-year Grants
Section一般
Research Field Physical properties of metals
Research InstitutionEhime University

Principal Investigator

NAKAI Kiyomichi  Ehime University, Faculty of Engineering, Associate Professor, 工学部, 助教授 (60038114)

Co-Investigator(Kenkyū-buntansha) OHTSUBO Hiroyuki  Ehime University, Faculty of Engineering, Research Associate, 工学部, 助手 (30036248)
OHMORI Yasuya  Ehime University, Faculty of Engineering, Professor, 工学部, 教授 (10233280)
Project Period (FY) 1995 – 1996
Project Status Completed (Fiscal Year 1996)
Budget Amount *help
¥1,800,000 (Direct Cost: ¥1,800,000)
Fiscal Year 1996: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1995: ¥1,300,000 (Direct Cost: ¥1,300,000)
KeywordsSuperlattice / Intermetallics / Superalloy / Phase decomposition / Lattice defect / Solute atom / Age-haedening / SADT / 相分解過程 / マッシブ組織 / 結晶方位関係 / 析出前段階 / 相安定性 / 相分離
Research Abstract

The mechanisms for decomposition processes of alpha-and beta-phases in Ti-Al base intermetallics have been analyzed in terms of crystallography.
1.the beta-phase stabilizes with increasing Zr and decomposes into Widmanstatten structure of alpha_2-phase by the Shear-Assisted Diffusional Transformation mechanism (SADT).
2.In 30-50at.%Al, (alpha_2+gamma) lamellar structure uncleates at the grainboundary gamma-allotriomorph by the SADT with the Blackburn orientation relationship.
3.Maasive structure, which consists of both alpha_2 and gamma, forms with the orientation relationships, {111}_<gamma>//{1011}_<alpha> and <110>_<gamma>//<1210>_<alpha>, in * 45at.%Al.
In Ni-base superalloy, the preprecipitation stages of ordered phases, which control the age-hardening, have been analyzed in terms of the interaction of solute atoms with lattice defects.
1.Quenched-in excess vacancies alter the nature of dislocations and enhance the trapping of solute atoms at the dislocations.
2.The trapping of solute atoms at the dislocations delays the ordered-phase precipitation as well as age-hardening, remarkably.

Report

(3 results)
  • 1996 Annual Research Report   Final Research Report Summary
  • 1995 Annual Research Report
  • Research Products

    (18 results)

All Other

All Publications (18 results)

  • [Publications] 仲井清眞: "Phase stability and decomposition processes in Ti-Al based intermetallics" Materials Science and Engineering A. 192/193. 922-929 (1995)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] 大森靖也: "Mechanism of Widmanstatten austenite formation in a δ/γ duplex phase stainless steel" ISIJ International. 35. 969-975 (1995)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] 大森靖也: "Effects of small amounts of B,Nb and Ti additions on nucleation and growth processes of intermediate transformation products in low carbon 3% Mn steels" ISIJ International. 35. 1001-1005 (1995)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] 仲井清眞: "Effects of lattice defect behaviors on preprecipitation stages of γ' and γ" phases in a Ni-base superalloy" ISIJ International. 36. 187-193 (1996)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] 仲井清眞: "Formation process of lamellar γ phase in a Ti-40.at%Al alloy" Mater.Trans.JIM. 37. 813-820 (1996)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] 大森靖也: "Crystallographic analysis of upper bainite in Fe-9%Ni-C alloys" Mater.Trans.JIM. 37. 1665-1671 (1996)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K.NAKAI,T.ONO,H.OHTSUBO and Y.OHMORI: "Phase stability and decomposition processes in Ti-Al based intermetallics" Mater.Sci.Engr.A. 192/193. 922-929 (1995)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Y.OHMORI,K.NAKAI,H.OHTSUBO and Y.ISSHIKI: "Mechanism of Widmanstatten austenite formation in a delta/gamma duplex stainless steel" ISIJ Intern. 35. 969-975 (1995)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Y.C.JUNG,K.NAKAI,H.OHTSUBO and Y.OHMORI: "Effects of small am ounts of B,Nb and Ti additions on nucleation and growth processes of intermediate transformation products in low carbon 3% Mn steels" ISIJ Intern. 35. 1001-1005 (1995)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K.NAKAI,Y.OHARA,H.OHTSUBO and Y.OHMORI: "Effects of lattice defect behaviors on preprecipitation stage of gamma'and gamma"phases in a Ni-base superalloy" ISIJ Intern. 36. 187-193 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] K.NAKAI,T.ONO,H.OHTSUBO and Y.OHMORI: "Formation process of lamellar gamma phase in a Ti-40at.% Al alloy" Mater.Trans.JIM. 37. 813-820 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] Y.OHMORI,Y.C.JUNG,H.UENO,K.NAKAI and H.OHTSUBO: "Crystallographic analysis of upper bainite in Fe-9% Ni-C alloys" Mater.Trans.JIM. 37. 1665-1671 (1996)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1996 Final Research Report Summary
  • [Publications] 仲井清眞: "Effects of lattice defect behaviors on preprecipitation stages of γ' and γ" phases in a Ni-base superalloy" ISIJ International. 36. 187-193 (1996)

    • Related Report
      1996 Annual Research Report
  • [Publications] 仲井清眞: "Formation process of lamellar phase in a Ti-40at.% Al alloy" Mater.Trans.JIM. 37. 813-820 (1996)

    • Related Report
      1996 Annual Research Report
  • [Publications] 大森靖也: "Crystallographic analysis of upper bainite in Fe-9% Ni-C alloys" Mater.Trans.JIM. 37. 1665-1671 (1996)

    • Related Report
      1996 Annual Research Report
  • [Publications] 仲井 清眞: "Phase stability and decomposition processes in Ti-Al based intermetallics" Materials Science and Engineering A. 192/193. 922-929 (1995)

    • Related Report
      1995 Annual Research Report
  • [Publications] 大森 靖也: "Mechanism of Widmanstatten austenite formation in a δ/γ duplex phase stainless steel" ISIJ International. 35. 969-975 (1995)

    • Related Report
      1995 Annual Research Report
  • [Publications] 仲井 清眞: "Effects of lattice defect behaviors on pre-precipitation stages of γ^1 and γ^<11> phases in a Ni-base superalloy" ISIJ International. (発表予定).

    • Related Report
      1995 Annual Research Report

URL: 

Published: 1995-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi