A Room-Temperature Diffusion Constant for Hydrogen in Proton-irradiated Steel

Abstract

RECENT measurements of hydrogen diffusion-rates in α-iron by Johnson and Hill¹ gave approximately 2 × 10⁻⁷ cm.²/sec. for the value of D at room temperature; and in steel by Frank, Lee, and Williams² gave approximately 1 × 10⁻⁷ cm.²/sec. Johnson and Hill measured re-emission of hydrogen from cylinders previously soaked in hydrogen at high temperatures and pressures, while Frank et al. used a mass spectrometer to measure the emission of hydrogen and deuterium from thin sheets. Frank, Swets and Fry³, observing the build-up of hydrogen permeating through thin sheets of steel, obtained for D at room temperature values about an order of magnitude higher.