Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-29T07:49:43.856Z Has data issue: false hasContentIssue false

Ion Irradiation Effects for Two Pyrochlore Compositions: Gd2Ti2O7 and Gd2Zr207

Published online by Cambridge University Press:  15 February 2011

S. X. Wang
Affiliation:
Department of Nuclear Engineering & Radiological Sciences, The University of Michigan, Ann Arbor, MI 48109, [email protected]
L. M. Wang
Affiliation:
Department of Nuclear Engineering & Radiological Sciences, The University of Michigan, Ann Arbor, MI 48109, [email protected]
R. C. Ewing
Affiliation:
Department of Nuclear Engineering & Radiological Sciences, The University of Michigan, Ann Arbor, MI 48109, [email protected]
K. V. Govindan Kutty
Affiliation:
Materials Chemistry Division, Indira Gandhi Center for Atomic Research, Kalpakkam 603 102, India
Get access

Abstract

Pyrochlore is an important nuclear waste form phase for actinide immobilization. Two synthetic pyrochlores, Gd2Ti2O7 and Gd2Zr2O7 were irradiated at various temperatures (25 K to 1073 K) by different ion species (1.5 MeV Xe+, 1.0 MeV Kr+, and 0.6 MeV Ar+). The titanate pyrochlore amorphized at relatively low doses (0.5 ∼ 0.6 dpa). Temperature dependence of the amorphization dose for titanate pyrochlore was measured, and the critical temperatures for amorphization were 1300 K, 1100 K and 950 K by 1.5 MeV Xe+, 1.0 MeV Kr+ and 0.6 MeV Ar+, respectively. The higher critical temperature for the heavier ion irradiation is consistent with an amorphization mechanism by which the heavier ion produces a larger cascade. The zirconate pyrochlore, Gd2Zr2O7, showed a strong amorphization “resistance”. Gd2Zr2O7did not become amorphous under 1.0 MeV Kr+ and 1.5 MeV Xe+ irradiation. After prolonged irradiation (up to 7 dpa) even at a temperature of 25 K, no amorphization was observed. The irradiated zirconate pyrochlore showed abundant dislocations as observed by TEM. The pyrochlore structure of Gd2Zr2O7 transformed to the fluorite structure after irradiation. The diffraction patterns of irradiated Gd2Zr2O7 showed the existence of short-range ordering of cations. The large difference between these two pyrochlores emphasizes the strong effect of chemical composition on radiation-induced amorphization.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

[1] Ringwood, A. E., Kesson, S. E., Ware, N. G., Hibberson, W., and Major, A., Nature 278 (1979) 219.Google Scholar
[2] Begg, B. D., Vance, E. R., Coradson, S. D., J. Alloys Comp. 271–273 (1998) 226.Google Scholar
[3] Lumpkin, G. R., Hart, K. P., McGlinn, P. J. and Payne, T. E., Radiochimi. Acta 66&67 (1994) 469.Google Scholar
[4] Ewing, R. C., Chakoumakos, B. C., Lumpkin, G. R. and Murakami, T., Mater. Res. Soc. Bull. 12 (1987) 58.Google Scholar
[5] Ewing, R. C. and Wang, L. M., Nucl. Instr. Meth. B65 (1992) 319.Google Scholar
[6] Lumpkin, G. R. and Ewing, R. C., Phys. Chem. Min. 16 (1988) 2.Google Scholar
[7] Clinard, F. W. Jr., Hobbs, L. W., Land, C. C., Peterson, D. E., Rohr, D. L. and Roof, R. B., J. Nucl. Mater. 105 (1982) 248.Google Scholar
[8] Weber, W. J, Wald, J. W. and Matzke, Hj., J. Nucl. Mater. 138 (1986) 196.Google Scholar
[9] Weber, W. J. and Hess, H. J., Nucl. Instr. Meth. B80/81 (1993) 1245.Google Scholar
[10] Weber, W. J., Hess, N. J. and Maupin, G. D., Nucl. Instr. Meth. B65 (1992) 102.Google Scholar
[11] Smith, K. L., Zaluzec, N. J. and Lumpkin, G. R., J. Nucl. Mater. 250 (1997) 36.Google Scholar
[12] Lumpkin, G. R., Smith, K. L. and Blake, R. G., Mat. Res. Soc. Symp. Proc. 412 (1996) 329.Google Scholar
[13] Moriga, T., Yoshiasa, A., Kanamaru, F. and Koto, K., Solid State Ionics 31 (1989) 319.Google Scholar
[14] Komyoji, D., Yoshiasa, A., Moriga, T. and Emura, S., Solid State Ionics 50 (1992) 291.Google Scholar
[15] Allen, C. W., Funk, L. L., Ryan, E. A. and Ockers, S. T., Nucl. Instrum. Meth. B40/41 (1989) 553.Google Scholar
[16] Wang, S. X., Wang, L. M., Ewing, R. C. and Doremus, R. H., J. Non-Cryst. Solids 238 (1998) 198.Google Scholar
[17] Weber, W. J., Ewing, R. C. and Wang, L. M., J. Mater. Res. 9 (1994) 688.Google Scholar
[18] Wang, S. X., Wang, L. M. and Ewing, R. C., Mat. Res. Soc. Symp. Proc. 504 (1998) in press.Google Scholar
[19] Wang, S. X., Wang, L. M., Ewing, R. C., Was, G. S. and Lumpkin, G. R., Nucl. Instr. Meth. B (1999) in press.Google Scholar
[20] Nakano, H., Urabe, K., Shirakami, T., Matsuo, A. and Kamegashira, N.. Mat. Res. Bull. 32 (1997) 1559.Google Scholar
[21] Dijk, M. P. van, Mijlhoff, F. C. and Burggraaf, A. J., J. Solid. State Chem. 62 (1986) 377.Google Scholar
[22] Moriga, T., Yoshiasa, A., Kanamaru, F. and Koto, K., Solid State Ionics 31 (1989) 319.Google Scholar
[23] Naguib, H. M. and Kelly, R., Radiat. Eff. 25 (1975) 1.Google Scholar
[24] Eby, R. K., Ewing, R. C. and Birtcher, R. C., J. Mat. Res. 7 (1992) 3080.Google Scholar
[25] Hobbs, L. W., Nucl. Instr. Meth. B 91 (1994) 30.Google Scholar
[26] Wang, S. X., Wang, L. M., Ewing, R. C. and Doremus, R. H., J. Non-Cryst. Solids 238 (1998) 214.Google Scholar