Hydrogen concentrations in the interface region of cadmium-plated steel

Measurements of H in the surface Cd-plated D6AC steel are reported. In the region of cadmium plating, the hydrogen concentration is uniformly 180 wt ppM. In the roughness region, the volume fraction of cadmium plating as well as the hydrogen concentration decrease with increasing depth. Therefore, it can be concluded that the hydrogen concentration is uniform throughout the plating and that the observed hydrogen gradient is the result of substrate roughness. The lack of complete coincidence between the concentration gradient and the roughness region is likely a result of the inaccuracy in establishing the average plating thickness over the 6.3-mm-diameter region probed