NEUTRON-INDUCED SWELLING OF MODEL FE-CR-MN-NI ALLOYS AND COMMERCIAL MANGANESE-STABILIZED STEELS

The addition of nickel to both simple and solute-modified Fe-Cr-Mn alloys leads initially to an increase in neutron-induced swelling. The addition of various minor solutes, particularly silicon, in general leads to a reduction in swelling. Depending on composition, thermomechanical condition and irradiation temperature, a wide variety of swelling behavior is observed in various commercial Fe-Cr-Mn alloys. There is some indication in the commercial alloys of massive formation of ferrite phases during irradiation at 420-degrees-C, leading to a reduction in the swelling rate.