[en] To assess the effects of long term, low dose rate neutron exposure on mechanical strength and ductility, tensile properties were measured on 12 % and 20 % cold worked (Cw) Type 316 stainless steel. Samples were prepared from reactor core components retrieved from the EBR-II reactor following final shutdown. Samples location were chosen to cover a dose range of 1-56 dpa at temperatures from 371-440 deg. C and dose rates from 0.5-5.8·10^-7 dpa/s. These dose rates are about an order of magnitude lower than those of typical EBR-II test sample locations. The tensile properties and corresponding microstructural characterization data will be presented in this paper. For the 12 % CW Type 316 stainless steel at a dose of 40 dpa the yield strength measured at 430 deg. C increases by ∼33 % over that of the fresh material and does not appear to saturate. This increase in strength correlates with microstructural features associated with radiation hardening. The 20 % CW Type 316 stainless steel also hardens under irradiation. At the highest dose achieved (47 dpa), the total elongation is reduced to < 1 % and fracture mode appears to the transition from pure ductile rupture to a fracture with more brittle features. The work hardening ability of both materials decreases with dose at a similar rate. The swelling in both materials is too low to affect the ultimate tensile strength