Dissolution of hydrogen from the gas in steel at room temperature

The purpose of this paper is to show that embrittlement of steel deformed in a hydrogen atmosphere is caused by hydrogen entering the crystal lattice. Tensile tests are made under pure compressed hydrogen gas. It is shown that the hydrogen penetrates steel before any fissures develop. The penetration depends on the time of exposure of fresh surface produced by straining but does not depend directly on the strain rate. The hydrogen distribution vs depth was measured. It agrees with a transient distribution calculated with an apparent solubility (1 cu cm per 100 g at 150 kp per sq cm) and an apparent diffusivity (1.3·10^?7 sq cm per sec).