THE EFFECT OF HYDROGEN ON THE YIELD AND FLOW-STRESS OF AN AUSTENITIC STAINLESS-STEEL

Tensile tests on 310s stainless steel foils, with and without hydrogen, were conducted at temperatures from 77 to 295 K and strain rates from 10(-3) to 10(-6)/s. Cathodic charging at elevated temperatures and at very low current densities was used to produce homogeneous solid solutions of hydrogen in this material. The yield stress and flow stress were found to increase with hydrogen content. Discontinuous yielding was observed at room temperature for specimens with hydrogen contents greater than 5 at. pct. The ductility, as measured by the strain to failure, was not critically dependent on hydrogen concentration at 77 and 295 K but was reduced at intermediate temperatures. The changes in mechanical behavior are discussed in terms of hydrogen-dislocation interactions.