材料期刊网

A stable face-centered cubic (fcc) stainless steel was H charged by exposing it to 9.8 MPa H gas at 300-degrees-C for 14 days. The concentration of H was determined to be 65 ppm. The mechanical testing at room temperature has shown that after H charging, the yield strength of the steel increases, and the behavior of the transient creep and the short-term stress relaxation becomes more intensive. All the results can be interpreted qualitatively, and part of the results can be quantitatively calculated by the theory of mobile dislocation density proposed by Alden. The analysis indicates that the essential effect of H is to obstruct the movement of dislocations, so that the strength and inelastic viscousness of the steel increase.