Determination of Hydrogen Diffusion Coefficients in F82H by Hydrogen Depth Profiling with a Tritium Imaging Plate Technique

Hydrogen diffusion coefficients in a reduced activation ferritic/martensitic steel (F82H) and an oxide dispersion strengthened F82H (ODS-F82H) have been determined from depth profiles of plasma-loaded hydrogen with a tritium imaging plate technique (TIPT) in the temperature range from 298 K to 523 K. Data of hydrogen diffusion coefficients, D, in F82H are summarized as D [m² s⁻¹] =1.1×10⁻⁷ exp(−16[kJ mol⁻¹]/RT). The present data indicate almost no trapping effect on hydrogen diffusion due to an excess entry of energetic hydrogen by the plasma loading, which results in saturation of the trapping sites at the surface and even in the bulk. In the case of ODS-F82H, data of hydrogen diffusion coefficients are summarized as D [m² s⁻¹] =2.2×10⁻⁷ exp(−30[kJ mol⁻¹]/RT) indicating a remarkable trapping effect on hydrogen diffusion caused by tiny oxide particles in the bulk of F82H.