Helium Migration in Iron
نویسنده
چکیده
A theoretical model of helium migration in body centred cubic (BCC)structure irons has been developed using the concept of the effective helium diffusion coefficient with the method of rate theory equations. Various helium migration mechanisms have been identified under irradiation conditions. Comparison of the effects of BCC structure and FCC structure on the effective diffusion coefficient was also made to examine the possibility of the application of BCC irons in fusion reactors. The effects of both external parameters such as temperature, helium production rate, radiation damage rate and internal parameters such as cavities, grain sizes and dislocations on the diffusion mechanisms have been investigated. It is hoped the model can be validated with experimental data from fusion nuclear reactors available in the future and be used to examine the consequences of the diffusion on helium bubble growth and coalescence.
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