Abstract
X-ray diffraction patterns of neutron irradiated Zircaloy-4 samples were obtained at the Brazilian Synchrotron Light Laboratory (LNLS) to study the effects of the fast neutron fluxes and post-irradiation thermal treatments on the zirconium hydride evolution. The high intensity and resolution of the synchrotron beam allowed to detect the (111)δ and (220)δ diffraction peaks of the ZrH1.5 + x (0 ≤ x≤ 0.16) δ-phase in unirradiated Zircaloy-4 samples having a hydrogen concentration as low as 0.2 at.% (20 wppm). Then, irradiated samples, that were taken from the Zircaly-4 core components of the argentine HWPR Atucha I Nuclear Power Plant (CNA-1) were studied with that radiation to detect the diffraction peaks of ZrH1.5 + x δ-phase particles precipitated in samples having hydrogen isotope concentration lower than 2 at.% (220 wppm). A significant increment of the (111)δ and (220)δ peak areas were observed at room temperature after post-irradiation thermal treatments at 600 °C during 4 h. These results indicate that after the annealing a hydrogen concentration between 35 to 70 wppm, which were apparently absent in the irradiated samples has precipitated at room temperature as zirconium hydrides. That amount was estimated from a (220)δ peak area versus the bulk H concentration regression line, made with unirradiated samples. These results get support to a hydrogen trapping hypothesis proposed in previous works. In addition, it has been shown that the zirconium hydride that precipitate in the irradiated samples have the equilibrium δ-ZrH1.5 + x cubic crystalline structure.
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Notes
Diffractometer Philips PW 3710.
The calculus only consider the fast neutron flux, that is En > 1 Mev, which produces the radiation damage in the zirconium matrix.
References
Vizcaíno P, Banchik AD, Abriata JP (2002) J Nucl Mater 304/2–3:96
Vizcaino P, Banchik AD, Abriata JP (2005) J Nucl Mater 336/1:54
Mc Minn A, Darby EC, Schofield JS (1998) Twelfth International Symposium: Zirconium in the Nuclear Industry, Toronto. ASTM, STP 1354. p 173
Vizcaino P, Banchik AD, Abriata JP (2004) Metall Mater Trans A 35A(8):2343
Zuzek E, Abriata JP, San Martín A (1990) Bulletin of alloy phase diagrams, vol 11, No. 4, p 385
Lewis MB (1984) J Nucl Mater 125:152
Chung HM, Daum RS, Hiller JM, Billone MC (2001) Zirconium in the Nuclear Industry: 13th International Symposium. ASTM STP 1423, Annecy, p 561
Yang WJS (1989) Effect of radiation on materials: 14th International Symposium, vol 1. ASTM STP 1046, Philadelphia, p 442
Kruger RM (1990) EPRI NP 6845-D
Acknowledgements
We are grateful for the support given by the Brazilian Synchrotron Light Laboratory (LNLS) under proposal D12A-XRD1–2805. In addition we are in debt with Aldo F. Craievich for his kindness assistance.
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Vizcaíno, P., Banchik, A.D. & Abriata, J.P. Hydrogen in Zircaloy-4: effects of the neutron irradiation on the hydride formation. J Mater Sci 42, 6633–6637 (2007). https://doi.org/10.1007/s10853-007-1525-x
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DOI: https://doi.org/10.1007/s10853-007-1525-x