Hardening of ferritic alloys at 288°C by electron irradiation

Tensile specimens of a commercially pure iron, an iron-copper alloy and two ferritic pressure vessel steels, were irradiated at 288 degrees C with 2.5 MeV electrons to doses of 2.82 x 10(23) and 9.35 x 10(23) e(-)/m(2), corresponding to calculated atomic displacement doses of 9.53 x 10(-4) and 3.16 x 10(-3) dpa, respectively. Tensile tests at room temperature showed dose-dependent increases in yield stress and ultimate tensile stress and reductions in uniform elongation, compatible with literature data for A533B steel neutron-irradiated at 288 degrees C to similar displacement levels. No systematic effect of copper content was discerned in these electron irradiations, contrary to expectations based on neutron irradiations. For the limited dose range over which direct comparison can be made, it is concluded that the hardening efficiency of electron irradiations per unit dpa at 288 degrees C is similar to that for neutron irradiations. (C) 2000 Elsevier Science B.V. All rights reserved.