Study of diffusion processes in the oxide layer of zirconium alloys

摘要

The largest application of zirconium alloys lies in the area of nuclear industry, where it is used for protection of fuel material. In the reactor core the coating material is affected by numerous adverse effects (e.g. T ～ 320 ° C, p ～ 15,5MPa, and radioactivity). Resistance of alloy is caused by formation of a protective oxide layer on the surface of the material. In the experiment when the alloy is oxidized due H_2~(18)O, we can examine diffusion through (18)~O oxide layer by means of nuclear reactions using methods of Ion Beam Analysis. Production of H_2~(18)O environment is very expensive. This is related to the development of equipment for small volumes of media used during exposure and thus reduction of the high cost of the experiment. Samples for the experiment were pipes made of Zr alloy E110 and Zircaloy, when some of them were pre exposed in UJP Praha Ltd. Laboratories. Samples were exposed in an experimental apparatus, where they are placed in the exposure cell. Analysis of the exposed samples was performed by Ion Beam Analysis on the Tandetron 4130 MC device on the NPI ASCR in Rez. The results show that experiments met the purpose of preparing the oxide layers using a small amount of media exposure. This confirmed the suitability of IBA methods for trace analysis and detection method for oxygen diffusion by oxide layer when exposed to environments containing (I8)~O. Further research is ongoing.