Probabilistic strength evaluation on superplastic 3Y-TZP ceramics

Baba, Shinichi; Shibata, Taiju; Yamaji, Masatoshi*; Sumita, Junya; Ishihara, Masahiro; Motohashi, Yoshinobu*; Sawa, Kazuhiro

Nihon Kikai Gakkai Kanto Shibu Ibaraki Koenkai (2004) Koen Rombunshu (No.040-3), p.61 - 62, 2004/09

no abstracts in English

Variations in mechanical properties of zirconia-base ceramics due to superplastic deformations

Kikuchi, Makoto*; Motohashi, Yoshinobu*; Ito, Tsutomu*; Sakuma, Takaaki*; Shibata, Taiju; Baba, Shinichi; Ishihara, Masahiro; Sawa, Kazuhiro; Hojo, Tomohiro*; Tsuji, Nobumasa*

Nihon Kikai Gakkai Kanto Shibu Ibaraki Koenkai (2004) Koen Rombunshu (No.040-3), p.57 - 58, 2004/09

no abstracts in English

Effects of neutron irradiation on some superplastic characteristics of tetragonal zirconia polycrystals containing 3 mol% yttria

Shibata, Taiju; Ishihara, Masahiro; Motohashi, Yoshinobu*; Ito, Tsutomu*; Baba, Shinichi; Kikuchi, Makoto*

Materials Transactions, 45(8), p.2580 - 2583, 2004/08

https://doi.org/10.2320/matertrans.45.2580

Fast neutrons (energy 1.610 J) were irradiated to tetragonal zirconia polycrystals containing 3 mol% yttria (3Y-TZP) at the fluence levels of 2.510 (Light irradiation) and 4.310 (Heavy irradiation) m. The irradiation caused no significant swelling in the 3Y-TZP specimens. After the neutron irradiation, superplastic characteristics were examined by tensile tests at a temperature range from 1623 to 1773 K with initial strain rates ranging from 5.010 to 1.6710s. It was found that the elongation to fracture of the irradiated specimens was quite small in comparison with the unirradiated ones. The apparent activation energy for the superplastic flow of the irradiated 3Y-TZP was fairly high, i.e., 781 and 693 kJ・mol for Light and Heavy irradiations, respectively. Atomic displacement damages and defects in the 3Y-TZP caused by the irradiation were thought to be main causes of these property changes.

Radiation damage effects in superplastic 3Y-TZP irradiated with Zr ions

Motohashi, Yoshinobu*; Kobayashi, Tomokazu*; Harjo, S.*; Sakuma, Takaaki*; Shibata, Taiju; Ishihara, Masahiro; Baba, Shinichi; Hoshiya, Taiji

Nuclear Instruments and Methods in Physics Research B, 206, p.144 - 147, 2003/05

https://doi.org/10.1016/S0168-583X(03)00702-X

The 3mol% yttria containing tetragonal zirconia polycrystals(3Y-TZP) were irradiated using 130MeV Zr ions in the TANDEM accelerator facility at Tokai Research Establishment, JAERI. Irradiation was performed with the fluence of 3.510 and 2.110 ions/m. Residual stress and changes in mechanical properties caused by the ion irradiation and the effects of the subsequent annealing are studied. The occurrence of compressive residual stresses and increases in hardness and fracture toughness were found at the surface regions of as-irradiated specimens. It was found from the subsequent annealing that these quantities decreased gradually with raising the annealing temperature and returned to that of un-irradiated state at around 1173K. A most probable cause of the increases in the hardness and fracture toughness after the irradiation may, therefore, be the residual compressive stresses left in the irradiated surface region.

Ion irradiation effect on superplastic deformation behavior of ceramic material

Shibata, Taiju; Ishihara, Masahiro; Motohashi, Yoshinobu*; Baba, Shinichi; Hoshiya, Taiji; Sakuma, Takaaki*

Nihon Kikai Gakkai Kanto Shibu Ibaraki Koenkai (2002) Koen Rombunshu (No.020-3), p.123 - 124, 2002/09

Applications of superplastic ceramics to nuclear energy fields are very promising because of their superior mechanical and thermal properties. In this study, Zr ion irradiation effects on superplastic deformation behavior of a typical superplastic ceramic, 3mol% yttria containing tetragonal zirconia polycrystals (3Y-TZP), were studied. Zr ions with 130MeV were irradiated on the 3Y-TZP specimens by TANDEM accelerator at fluence levels of 3.5x10 and 2.1x10ions/m. Their mechanical properties were examined by three-point bending test at elevated temperatures after the irradiation. As a result, at the temperature range from the room temperature to 1473K, any obvious irradiation effects were not found by the bending test. On the other hand, at the range from 1623K to 1773K, it was found that the superplastic deformation behavior was changed by the Zr ion irradiation. The activation energy of superplastic deformation was increased with increasing the irradiation fluence.

Experimental investigation on the effect of superplastic deformation on the specific heat of a zirconia-based ceramic

Wan, C.*; Shibata, Taiju; Baba, Shinichi; Ishihara, Masahiro; Hoshiya, Taiji; Motohashi, Yoshinobu*

Netsu Bussei, 16(2), p.58 - 63, 2002/06

https://doi.org/10.2963/jjtp.16.58

no abstracts in English

Mechanical property of superplastic-deformed ceramics by micro-indentation method

Shibata, Taiju; Ishihara, Masahiro; Takahashi, Tsuneo*; Motohashi, Yoshinobu*; Hayashi, Kimio

JAERI-Research 2001-024, 24 Pages, 2001/03

JAERI-Research-2001-024.pdf:6.25MB

no abstracts in English

Effects of superplastic deformation on thermal and mechanical properties of 3Y-TZP ceramics (Review)

Ishihara, Masahiro; Shibata, Taiju; Baba, Shinichi; Hoshiya, Taiji; Wan, C.*; Motohashi, Yoshinobu*

Proceedings of OECD/NEA 2nd Information Exchange Meeting on Basic Studies in the Field of High-temperature Engineering, p.113 - 124, 2001/00

no abstracts in English

Design and development of supporting system for ITER/CDA blanket box structure

Nishio, Satoshi; ; Shimizu, Katsusuke*; Koizumi, Koichi; Abe, Tetsuya; Tada, Eisuke

JAERI-M 93-091, 92 Pages, 1993/03

JAERI-M-93-091.pdf:2.69MB

no abstracts in English