IRRADIATION EFFECTS ON MECHANICAL-PROPERTIES OF LOW ACTIVATION MN-SI-CR STEELS

Alloying with silicon and manganese instead of nickel was calculated to be effective for the reduction of radioactivity after exposure to 14 MeV neutrons. Two compositions, Fe-17%Mn-4.5%Si-6.5%Cr and Fe-22%Mn-4.5%Si-6.5%Cr-0.2%N, were chosen for new low activation steels. Tensile tests were performed using miniature specimens at temperatures ranging between 4.2 and 473 K. Both steels showed high strength and ductility. After neutron irradiation to 1.6 x 10(25) n/m2 at < 523 K, both steels retained good ductility at temperatures higher than 170 K.