Tritium release from an Al-Mg-Li alloy irradiated by 14 MeV neutrons
Abstract
An alloy of Al-Mg-Li was irradiated at room temperature by 14 MeV neutrons using RTNS-II of Lawrence Livermore National Laboratories up to the fluence of 1.2 × 10 17n/ cm2. The release rate of tritium from the irradiated alloy was measured in a temperature region from 573 to 823 K. The measured release rate was analysed with a diffusion-controlled model and the diffusion coefficient of tritium in the alloy was determined as follows: D=2.64×10 -3 exp - {36.1±3.4}/{RT/(kJ/mol)} cm 2/s (670 <T < 873 K) , D=4.12×10 -4 exp - {129.1±1.5}/{RT/(kJ/mol)} cm 2/s (573 <T < 670 K) . These diffusion coefficients were interpreted in terms of characteristics of the tritium release behavior of the present alloy: The tritium release rate at temperatures above 670 K is completely controlled by the diffusion process in the alloy which is not influenced by any trapping effect, while the release process at temperatures below 670 K is influenced by a hindering effect due to an oxygen contamination on the specimen surface and the large activation energy should be ascribed to that effect. It was also suggested that the possibility of the trapping effects due to the radiation damage induced by 14 MeV neutrons could not completely be excluded.
- Publication:
-
Journal of Nuclear Materials
- Pub Date:
- September 1988
- DOI:
- 10.1016/0022-3115(88)90169-9
- Bibcode:
- 1988JNuM..158..202S