Oxygen, Hydrogen and Main Alloying Chemical Elements Partitioning Upon Alpha←→Beta Phase Transformation in Zirconium Alloys


Article Preview

Due to their adequate properties, zirconium alloys are the reference materials for the nuclear fuel cladding tubes of Light Water Reactors (LWR). During some hypothetical accidental High Temperature (HT) transients, the materials should experience heavy steam oxidation and deep metallurgical evolutions. This promotes Alpha-Beta phase transformations and an associated strong partitioning of oxygen/hydrogen and of the main chemical alloying elements (Nb, Sn, Fe and Cr). Moreover, it has been shown quite recently that such chemical elements partitioning during on-cooling Beta-to-Alpha transformation can strongly impact the residual mechanical properties of HT oxidized materials. Thus, it appeared that it was important to better quantify and, if possible, to compute the quite complex phase equilibrium that occurs in multi-alloyed zirconium materials in the presence of both oxygen and hydrogen. For that, systematic studies have been performed on industrial alloys, charged with oxygen and/or hydrogen. After applying different heating/cooling scenarii, both Electron Microprobe using Wave Dispersive Spectrometry (WDS) and Nuclear Microprobe using Elastic Recoil Detection Analysis (ERDA) have been applied. Finally, to support the observed chemical elements partitioning between the Alpha and Beta allotropic phases, some thermodynamic calculations have been performed thanks to the development and the use of a specific thermodynamic database for zirconium alloys called “Zircobase".



Solid State Phenomena (Volumes 172-174)

Edited by:

Yves Bréchet, Emmanuel Clouet, Alexis Deschamps, Alphonse Finel and Frédéric Soisson




J. C. Brachet et al., "Oxygen, Hydrogen and Main Alloying Chemical Elements Partitioning Upon Alpha←→Beta Phase Transformation in Zirconium Alloys", Solid State Phenomena, Vols. 172-174, pp. 753-759, 2011

Online since:

June 2011




[1] J. -C. Brachet, V. Vandenberghe-Maillot et al., Hydrogen Content, Pre Oxidation and Cooling Scenario Influences on Post-Quench Mechanical Properties of Zy-4 and M5® Alloys …, Journ. of ASTM International, Vol. 5, No. 5, Paper ID JAI101116, (2008).

DOI: https://doi.org/10.1520/jai101116

[2] F. Stein, G. Sauthoff, and M. Palm, J. Phase Equilib., Vol. 23, No. 6, 2002, p.480–494.

[3] C. Toffolon-Masclet et al., Contribution of thermodynamic calculations to metallurgical studies of multi-component zirconium based alloys, Journ. of ASTM International, 5, (2008), paper JAI101122, available online at www. astm. org.

DOI: https://doi.org/10.1520/jai101122

[4] N. Dupin et al., A Thermodynamic Database for Zr Alloys , JNM 275 (1999), 287-295.

[5] J. Jourdan, PhD Thesis manuscript, CEA report-R-6238, (2010).

[6] G. Trégo, Modélisation du comportement en fluage à haute température dans le domaine biphasé α+β de l'alliage M5 ", proceeding of French national " MECAMAT , symposium, Aussois, France (January 26-30th. 2009).

[7] C. Desgranges, C. Toffolon-Masclet et al., Simulation of Oxygen Diffusion during High Temperature Oxidation of Zr base Alloys , this conference.

[8] J. -C. Brachet et al., Mechanical behavior at Room Temperature and Metallurgical study of Low-Tin Zy-4 and M5TM after oxidation at 1100°C and quenching", Proc. of TCM on "Fuel behavior under transient and LOCA conditions, IAEA, Halden-Norway, Sept. 10-14, (2001).

[9] A. Stern, PhD Thesis manuscript, CEA report-R-6197, (2008).

[10] V. Vandenberghe et al., Influence of the Cooling Scenario on the Post-Quench Mechanical Properties of Pre-Hydrided Zircaloy-4 Fuel Claddings after high Temperature Steam Oxidation (LOCA Conditions), Proceedings of 2010 LWR Fuel Performance / TopFuel / WRFPM Orlando, Florida, USA, Sept. 26-29, 2010, Paper 096.

[11] C. Raepsaet, et al., Quantification and local distribution of hydrogen within Zircaloy-4 PWR nuclear fuel cladding tubes at the nuclear microprobe of the Pierre Süe laboratory from µERDA, Journ. of Nucl. Instr. and Methods in Physics Research B 266 (2008).

DOI: https://doi.org/10.1016/j.nimb.2008.03.041

[12] R. Jerlerud-Perez, C. Toffolon-Masclet, J.M. Joubert and B. Sundman, The Zr-Sn Binary System : New Experimental Results and Thermodynamic Assessment, CALPHAD, 32, (2008), 593-601.

DOI: https://doi.org/10.1016/j.calphad.2008.04.001