Repairing irreversible hydrogen-induced damages using electric current pulse

摘要

The synergistic effect of hydrogen and stress will cause various damages to metallic materials, such as hydrogen-induced cracks, blisters, voids, which would cause unpredictable failure of the metallic materials. In this study, the mechanical properties of high-strength steel with hydrogen damages were effectively restored after electropulsing treatment. The reasons are that the hydrogen content was reduced to a lower concentration on the one hand, and the hydrogen damages (microcracks and voids) were partially repaired on the other hand. Essentially, the introduction of an applied electric field increases the free energy of the system and reduces the energy barrier for diffusion of hydrogen, resulting in faster diffusion of hydrogen and lower hydrogen content. Simultaneously, the temperature rises and compressive stress induced by electropulsing are accountable for the healing of hydrogen damages. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.