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

Effect of the Strength of the Parent Phase on the DrivingForce for the Martensitic Transformation of Partially Stabilized Zirconia

Research Project

Project/Area Number 06650728
Research Category

Grant-in-Aid for General Scientific Research (C)

Allocation TypeSingle-year Grants
Research Field Physical properties of metals
Research InstitutionTottori University

Principal Investigator

HAYAKAWA Motozo  Tottori Univ., Faculty of Engineering, Professor, 工学部, 教授 (60093621)

Co-Investigator(Kenkyū-buntansha) MORINAGA Masahiko  Nagoya Univ., Faculty of Engineering, Professor, 工学部, 教授 (50126950)
岡 宗雄  鳥取大学, 工学部, 教授 (60029866)
Project Period (FY) 1994 – 1995
Project Status Completed (Fiscal Year 1995)
Budget Amount *help
¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1995: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 1994: ¥1,500,000 (Direct Cost: ¥1,500,000)
KeywordsTetragonal Zirconia Polycrystals / Yttria Doped / Ceria Doped / Grain Size Dependence on Hardness / Composition Dependence on Hardness / Martensitic Transformation Temperature / Isothermal Martensitic Transformation / セリア添加
Research Abstract

1. The effect of the composition and the grain size on the strength of the parent phase
TZP (Tetragonal Zirconia Polycrystals) specimens were prepared with five different composition, namely 3Y,0.75Y-3Ce, 1.5Y-6Ce, 2.25Y-9Ce, and 12Ce, where Y and Ce denote mol% of Y_2O_3 and CeO_2 in zirconia, respectively. The grain size of the specimens was modified by post sinter annealing.
The strength of the tetragonal phase as measured by Vickers hardness tester decreased monotonically with increasing ceria content (or decreasing yttria content), but the rate of the decrease became increasingly steep with increasing ceria content. The grain size dependence was reasonably well approximated by the Hall-Petch relation. Thus, the hardness of the two extreme compositions was represented by the following empirical equations :
Hv=1250-0.90 (T-293) +100 (d^<-0.5>-1.21) for 3y-TZP
Hv= 950-0.68 (T-293) +430 (d^<-0.5>-0.72) for 12Ce-TZP
where T denote temperature in K and d grain size in micrometer.
2. The effect of the composition on the transformation temperature
The specimens used in the above experiment did not transform by cooling as low as liquid nitrogen temperature except a few. Thus, specimens with lower yttria content were prepared for the Ms and As temperature measurement. These temperatures were represented by the follwing equations :
As=1459-269Y for0<Y<3
Ms=1279-364Y for0<Y<1.5
Since the Ms of 2Y was below 77K,the driving force as measured by As-Ms rapidly increased when Y content exceeds 2mol%. This is unlikely to be explained by the free energy change or hardness increase with the increasing Y content. A further study is necessary to explain this drastic change of Ms temperature.

Report

(3 results)
  • 1995 Annual Research Report   Final Research Report Summary
  • 1994 Annual Research Report
  • Research Products

    (8 results)

All Other

All Publications (8 results)

  • [Publications] 早川元造,岡 宗雄: "ジルコニアセラミックスのマルテンサイト変態" 熱処理. 34. 315-320 (1994)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1995 Final Research Report Summary
  • [Publications] 早川元造,岡 宗雄: "ジルコニア系セラミックスのマルテンサイト変態と" まてりあ. 33. 1481-1488 (1994)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1995 Final Research Report Summary
  • [Publications] M. Hayakawa, Y. Inaue, M. Oka, H. Nakagawa: "Martensitic Transformation and Mechanical Pnoperties of (Y, Ce)-Tefragonal Zircontia Polycrystals" Materials Transaction JIM. 36. 729-734 (1995)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1995 Final Research Report Summary
  • [Publications] M. Hayakawa, T. Okuda, M.Oka: "Grain Size Dependence of the Martensitic Transformation fo Yttria Doped TZP" Proc, ICOMAT-95. (in press). (1996)

    • Description
      「研究成果報告書概要(和文)」より
    • Related Report
      1995 Final Research Report Summary
  • [Publications] M.Hayakawa, Y.Inoue, M.Oka and H.Nakagawa: ""Martensitic Transformation and Mechanical Properties of (Y,Ce) -Tetragonal Zirconia Polycrystals"" Materials Transaction JIM. 33. 1481-1488 (1995)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1995 Final Research Report Summary
  • [Publications] M.Hayakawa, T.Okuda and M.Oka: ""Grain Size Dependence of the Martensitic Transformation of Yttria Deped Tetragonal Zirconia Polycrystals" Proc.ICOMAT-95. (in press). (1996)

    • Description
      「研究成果報告書概要(欧文)」より
    • Related Report
      1995 Final Research Report Summary
  • [Publications] 早川元造・岡宗雄: "ジルコニア系セラミックスのマルテンサイト変態と強靱化" まてりあ. 33. 1481-1488 (1994)

    • Related Report
      1994 Annual Research Report
  • [Publications] 早川元造・岡宗雄: "ジルコニアセラミックスのマルテンサイト変態" 熱処理. 34. 315-320 (1994)

    • Related Report
      1994 Annual Research Report

URL: 

Published: 1994-04-01   Modified: 2016-04-21  

Information User Guide FAQ News Terms of Use Attribution of KAKENHI

Powered by NII kakenhi