Hardening and intergranular embrittlement in neutron-irradiated ferritic alloys

Abstract

Abstract The characteristics of hardening and integranular embrittlement induced during neutron irradiation (0.94 × 10 23 n m −2 at 395 °C) in ferritic alloys doped with copper, phosphorus and/or carbon have been investigated using small punch test techniques. The effect of neutron irradiation on hardening was found to be greater in alloys doped with copper and/or phosphorous than in carbon-containing alloys. It has been shown that the great magnitude of irradiation-induced hardening observed for the copper- and/or phosphorus-containing alloys is attributed to an increase in both the athermal and thermal stress components. The neutron irradiation produced a more substantial increase in the ductile-brittle transition temperature in the copper-doped alloy compared with the other alloys. Intergranular and transgranular fracture occurred in the alloys doped without and with carbon respectively. The neutron irradiation did not alter the fracture mode.