• Published : 2009.03.30


High burn-up transformation process in low temperature nuclear fuel oxides material was observed in the early sixties in LWR $UO_2$ fuels, but not studied in depth. Increasing progressively the fuel discharge burn-up in PWR power plants, this material transformation was again observed in 1985 and identified as an important process to be accounted for in the fuel simulations due to its expected consequence on fuel heat transfer and therefore on the fission gas release. Fission gas release was one of the major concerns in PWR fuels, mainly during transient or accidents events. The behaviour of such a material in case of rod failure was also an important aspect to analyse. Therefore several national and international programs were launched during the last 25 years to understand the mechanisms leading to the high burn-up structure formation and to evaluate the physical properties of the final material. A large observations database has been acquired, using the more sophisticated techniques available in hot cells. This large database is discussed in this paper, providing basis to build an engineering-model, which is based on phenomenological description data and information accumulated. In addition this paper has the ambition to construct the best logical model to understand restructuring.


  1. D.Baron, "Abnormal Porosity Buildup in the Fuel Periphery at High Burn-up", 9th HBEP Review, Wengen (Switzerland), june 9th, 1986.
  2. M.L.Bleiberg, R.M.Berman and B.Listman, proceedings Symposium on Radiation Damage in solids and Reactor Materials, IAEA, Vienna 1963, pp319
  3. J.O.Barner, M.E.Cuningham, M.D.Freshley, D.D Lanning, "High Burn-up Effect Program - Final Report", HBEP-61, 1990, Battelle Pacific Northwest Laboratories.
  4. D.Baron, B.Bordin-Lhermitte, J-P Piron , "an Attempt to simulate the Porosity Build-up in the Rim at High Burn-up", IAEA Technical Commitee Meeting on Advances in Pellet Technology for improved Performance and High Burn-up - Toranomon Pastral, TOKYO, JAPAN, October 26th - November 1st, 1996.
  5. M.Kinoshita et al, "Final Report of High Burn-up Rim Project (HBRP), CRIEPI (2001).
  6. M.Kinoshita et al, "High Burn-up Rim Project II, Irradiation and examination to investigate rim-structured fuel" ANS Meeting, april 9-13 2000, Park City, USA (ANS CD-Rom).
  7. L.Desgranges, B.Pasquet, "Measurements of Xenon in Uranium dioxide (UO2) with SIMS", Journal of Nucl. Mat. 215 (2004) pp 245-551
  8. J.Lamontagne, J.Noirot, L.Desgranges, T.Blay, B.Pasquet, I.Roure, "Detection of Gas Bubbles by SIMS in irradiated Materials", Microchemica Acta 145 (2004) pp91-94.
  9. J.Spino, D.Baron, M.Coquerelle, A.D.Stalios, "High Burn-up Rim Structure: Evidence that Xenon Depletion, Pore Formation, and Grain Subdivision start at Different Local Burn-ups", Journal of Nucl. Mat. 256 (1998) 189-196.
  10. Jeff Rest, G.L. Hofman, "An alternative explanation for evidence that Xenon depletion, pore formation and subdivision begin at different burn-ups", Journal of Nucl. Mat. 277(2000), pp 231-238.
  11. J.Spino, D.Papaioannou, "Lattice contraction in the rim zone as controlled by recrystallization : additional evidence", letter to the editor, Journal of Nucl. Mat. 372 (2008) pp 416-420.
  12. N.Lozanno, L.Desgranges, "High Magnification SEM Observations for two types of Granularity in a High Burn-up PWR Fuel Rim", Journal of Nucl. Mat. 257 (1998) p78.
  13. M. Kinoshita, T. Sonoda, S. Kitajima, A. Sasahara, E. Kolstad, Hj. Matzke, V.V. Rondinella, A.D. Stalios, C.T. Walker, I.L.F. Ray, M. Sheindlin, D. Halton, C. Ronchi, "High Burnup Rim Project (II) Irradiation and Examination to Investigate Rim-Structured Fuel", Proc. Int. Conf. on LWR Fuel Performance, ANS, Park City, Utah, April 9-14, 2000, p. 590-603.
  14. J.Soullard, "Contribution a l'etude des defauts de structure dans le bioxyde d'Uranium", PHD work presented on October 8th, 1976, faculte des Sciences de Poitiers, report CEA-R-4882 CEN Fontenay-aux-roses.
  15. J.Noirot, L.Desgranges, J.Lamontagne, "Detailed Characterisations of High Burn-up Structures", Journal of Nucl. Mat. 372 (2007) pp318-339.
  16. T. Sonoda, M. Kinoshita, I.L.F. Ray, T. Wiss, H. Thiele, D. Pellottiero, V.V. Rondinella, Hj. Matzke, "TEM observation on irradiation-induced microstructural evolution in high burn-up UO2 disk fuel", Nucl. Instr. Meth. Phys. Res. B191 (2002) 622-628.
  17. Kazuhiro Nogita and Katsumi Une, "Radiation-induced Microstructural Change in High Burnup UO2 Fuel Pellets", Nuclear Instruments and Methods in Physics Research B 91 (1994) 301-306.
  18. J.Jonnet, "A Contribution to the Understanding of the High Burn-up Structure Formation in Nuclear Fuel", These soutenue a L'Institut National Polytechnique de Lorraine, Mecanique et Energetique, 9 Janvier 2007.
  19. M. Iwasawa, Y. Chen, Y. Kaneta Yasunori, T. Ohnuma, H-Y. Geng, M. Kinoshita, "First-principles calculation of point defects in uranium dioxide", Materials transactions ISSN 1345-9678, vol. 47, no11, pp. 2651-2657, 2006
  20. W.H. Hall, G.K.Williamson, Proc. Phys. Soc. A62, 631, 1959.
  21. G.K.Williamson, W.H. Hall, "XRAY line broadening from filed Aluminium and Wolfran", acta Mettall. 1, pp22-31, 1953.
  22. Paul Van Uffelen, "Contribution to the Modelling of Fission Gas Release in Light Water Reactor Fuel", PhD report January 8th 2002, University of Liege, Faculty of Applied Sciences, Nuclear Engineering Department
  23. K.Une, M.Hirai, K.Nogita, et al, "Rim Structure Formation and High Burn-up Fuel Behaviour of large-grained $UO_2$ Fuels", Journal of Nucl. Mat. 278 (2000) no1 pp54-63.
  24. D.Baron presentation, Proceedings on CD-ROM (2004) P1-1 ORA/PRO. RNK: V/458/04 Van Uffelen et al, International Workshop on the High Burn-Up Structures in Nuclear Fuels.
  25. M.Kinoshita, Takanori Kameyama et al, "HBRP_NT - Final report no2", July 2005 (restricted access).
  26. Laurent Bourgeois, PhD "Contribution a l'Etude du role des dopants dans la densification et la croissance cristalline du dioxyde d'Uranium", INPG PhD presentation June 17th, 1992, CEA Report CEA-R-5621, 1993.
  27. J.Noirot, L.Desgranges, P.Marimbeau, "Fission Gas Behavior in Water reactor Fuels", Seminar Proceedings Cadarache, France September 26-29 2000, NEA/OECD, NEA #03053, 2002 p 223 (ISBN 92-64-16715-X).
  28. J.Spino, P.Peerani, "Oxygen Stochiometry Shift of Irradiated LWR-fuels : a Review. Implications for gas release", Journal of Nucl. Mat. 375 (2008) pp 8-25.
  29. K.Une, S.Kashibe, K.Hayashi, "Fission Gas Release Behavior in High Burn-up $UO_2$ Fuels with develloped Rim Structure", Actinides 2001, Hayama, Japan, Nov 4-9, 2001.
  30. D.Baron, R.Masson, J-M.Gatt, J.Spino, D.Laux, "Evolution of the Fuel Mechanical Properties with Burn-up, an Extensive European Experimental Program", 2005 Water Reactor Fuel Performance JNS-ENS-ANS meeting, October 2-6, 2005, Kyoto, Japan.
  31. C.Ronchi, M. Sheindlin, D Staicu, M. Kinoshita, "Effect of burn-up on the thermal conductivity of Uranium dioxyde up to 100.000 MWd t-1.", J. Nucl Mater. 327 (2004), p. 58.
  32. V.V.Likhanskii, O.V. Khoruzhii, A.A Sorokin, "Physical Model of Rim-layer formation in $UO_2$ Fuels", International Workshop on the High Burn-up Structure in Nuclear Fuels, TUI Karlsruhe, June 28th-30th, 2004.
  33. M.Kinoshita, "Towards the mathematical Model of Rim Structure Formation", Journal of Nucl. Mat. 248 (1997) 185-190.
  34. J.Rest, "A model for the influence of microstructure, precipitate pinning and fission gas behavior on irradiation-induced recrystallisation of nuclear fuels" Journal of Nucl. Mat. 326(2004) pp 175-184.
  35. J.Rest, "A model for the effect of the progression of irradiated-induced recrystallisation from initiation to completion on swelling of UO2 and U-10Mo nuclear fuels", Journal of Nucl. Mat. 346 (2005) pp 226-232.
  36. G.Khvostov, Vladimir Novikov, Anatoli Medvedev, Serguey Bogatyr, "Approaches to Modeling of High Burn-up Structure and Analysis of its Effects on the Behaviour of Light Water Reactor Fuels in the START-3 Fuel Performance Code", paper 1104, 2005 Water Reactor Fuel Performance JNS-ENS-ANS meeting, October 2-6, 2005, Kyoto, Japan.
  37. Frederico Garrido, "Crystallochemistry of Anion-excess Fluorite-type Uranium Oxides", 4th NXO meeting, Accelerator and Computer Science to Study Fission Irradiation on Fuel Materials, Tokyo University, November 13-14, 2007.
  38. J-P.Berton, D.Baron, M.Coquerelle, "Chemical Stability and Physical Properties of Cesium Uranates", IAEA TCM, TOKYO, Japan, 29 October to 1 November 1996.
  39. J-P.Hiernaut, T.Wiss, J-Y.Colle, H.Thiele, C.T.Walker, W.Goll, R.J.M.Konings, "Fission product release and microstructure changes during laboratory annealing of a very high burn-up fuel specimen", Journal of Nucl. Mat. 377(2008) pp313-324.
  40. H.J.Geng, Y.Chen, Y.Kaneta, M.Kinoshita, Phys.Rev. B77, 180101, 2008.
  41. H.J.Geng, Y.Chen, Y.Kaneta, M.Iwasawa, T.Ohnuma, M.Kinoshita, Phys.Rev. B 77, 104120, 2008.
  42. C.Walker, V.Rondinella, D.Papaioannou, S.Van Vinckel, W.Goll, R.Manzel, Journal of Nucl. Mat. 345 (2005) 192.
  43. H.J.Matzke, "Oxygen potential in the rim region of high burn-up UO2 fuel", Journal of Nucl. Mat. 208 (1994) 18-24.
  44. H.J.Matzke, "Oxygen potential measurements in high burn-up LWR UO2 fuel ", Journal of Nucl. Mat. 223 (1995) 1-5.
  45. I.L.F.Ray, H.J.Matzke, H.A.Thiele, M.Kinoshita, "An electron microscopy study of the RIM structure of a UO2 fuel with a high burn-up of 7.9 % FIMA", Journal of Nucl. Mat. 245 (1997) 115-123.
  46. M.Kinoshita, T.Kameyama, S.Kitajima, H.J.Matzke, "Temperature and fission rate effects on the rim structure formation in a UO2 fuel with a burn-up of 7.9 % FIMA", Journal of Nucl. Mat. 252 (1998) 71-78
  47. K.Lassmann, C.T.Walker, J.Van de Laar, F.Lindstrom, "Modelling the high burn-up UO2 Structure in LWR Fuel", Journal of Nucl. Mat. 226 (1995) pp 1-8.
  48. J.Nakamura (JAERI), "Strain of Crystal Lattice in Irradiated Fuel", Fuel Safety Research Meeting, May 16-17 2007.
  49. P.Guedeney, M.Trotabas, M.Boschiero, C.Forat, "FRAGEMA Fuel Behaviour Characterization at High Burn-up", ANS/ENS International Topical Meeting on LWR Fuel Performance, Avignon (France), April 21-24, 1991, P 627, Vol 2.
  50. I.L.F.Ray, H.J.Matzke, "Observation of a high burn-up rim-type structure in an advanced Plutonium-Uranium carbide", Letter to the Editors, Journal of Nucl. Mat. 250 (1997) 242-243.