LATTICE HARDENING AND ANOMALOUS SOFTENING OF IRON AND STEEL CAUSED BY ELECTROLYTIC HYDROGEN CHARGING

In order to clarify the intrinsic effect of dissolved hydrogen on the mechanical properties of iron and steel, the results obtained in a tensile experiment were critically examined with special emphasis on some side effects caused by the electrolytic method of hydrogen charging. The introduction of dissolved hydrogen always raised the flow stress of iron and steel, showing hydrogen-induced lattice hardening. This should be considered as an intrinsic change in bulk property of materials, because it was independent of specimen size for larger specimens.