59 Analytical and Numerical Calculation of Hydrogen Desorption Rate During TDS Analysis Using the Kissinger Formula and the McNabb-Foster Model Available to Purchase

The simple Kissinger formula dX/dt=Aexp(-E_d/RT) has long been considered to be only applicable to the desorption with negligible diffusion. The present study has shown that this formula is not only applicable to detrapping-controlled desorption but also to diffusion-controlled desorption during TDS analysis provided that both the initially uniformly distributed hydrogen within the specimen is released to some extent prior to thermal analysis and the existence of effective diffusivity is assumed for the latter case. Simulation results for typical trapping situations have been compared to the numerical calculation which was carried out according to the rigid McNabb-Foster model, and a good agreement has been found between them under an appropriate assumption.