HYDROGEN PERMEABILITY AND DELAYED FAILURE OF POLARIZED MARTENSTIC STEELS

Characteristics were directly correlated under cathodic and anodic polarization for 9-4- 45 and 4340 high strength steels. With increasing anodic applied potential, the 9-4- 45 displayed decreased times to failure, increased hydrogen permeability and surface pitting. The time to failure in 4340 did not respod to anodic polarization, there was no hydrogen permeation, and no pitting. It is apparent that increased susceptibility to delayed failure under anodic potentials does not, per se, rule out the availability of hydrogen.