DECREASE OF DUCTILITY DUE TO HYDROGEN IN FE-CR-MN AUSTENITIC STEEL

Under 14 MeV neutron irradiation, hydrogen is produced due to the (n, p) reaction. One of the significant effects of hydrogen is austenitic steels is a decrease in ductility. In this investigation the objective is to clarify the behavior of hydrogen and to investigate the effect on the ductility in Fe-Cr-Mn austenitic steel. Hydrogen doping was simulated by electrolytic charging. In internal friction measurements, the hydrogen peak was found at 300 K, when the frequency was 600 Hz. This peak increased with charging time and saturated. The saturated peak height increased with the degree of cold work. This suggests that more hydrogen atoms are absorbed into cold worked materials. The work hardening coefficient and the ductility at the maximum load decreased with increasing hydrogen amount. The mechanism of the decrease in ductility is discussed in terms of dislocations behavior.