A Reexamination of the Trapping of Hydrogen in Iron and Steel

Abstract

The apparent hydrogen diffusivity data for pretreated pure iron and steel membranes have been analysed for hydrogen-trapping effects. Modified equations, valid for the appropriate boundary conditions of charging, have been derived to compute the trap density from the apparent diffusivity. In general, the traps are saturable in nature. The dependence of diffusivity of hydrogen in iron and steel on the charging current density or overvoltage indicates trapping of hydrogen at dislocations and grain/interfacial boundaries. © 1993, The Japan Institute of Metals. All rights reserved.