A method to calculate hydrogen trap binding energy in austenitic stainless steel using local equilibrium model

摘要

The trap binding energy is an important parameter to understand the behavior of hydrogen in metals. Unfortunately, a reliable and practical method to calculate the hydrogen trap binding energy of austenitic stainless steels (gamma-SS) is still lacking. In this work, the validity of local equilibrium model (LEM) for simulating the hydrogen desorption spectrum of gamma-SS is studied first. Results show that LEM can be used to calculate the hydrogen thermal desorption spectrum of gamma-SS reliably when the specimen thickness and heating rate are small enough. Then, an effective hydrogen pre-discharging method is used to simplify the numerical fitting of hydrogen desorption spectrum, and a method to calculate the hydrogen trap binding energy in gamma-SS is developed using LEM. Finally, the hydrogen trap binding energy of dislocation in S30408 is calculated to be 26.3 kJ/mol on the basis of experimental hydrogen thermal desorption spectrum using the developed method. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.