Investigation of microstructure and mechanical properties of low dose neutron irradiated HT-9 steel

•Neutron irradiation has been carried out on HT-9 steel.•Microstructure of the irradiated HT-9 steel has been investigated using XRD.•There is an increase in dislocation density in the irradiated sample.•Tensile tests have been carried out to determine the changes in mechanical properties due to irradiation.•Yield stress and strain rate sensitivity increased due to irradiation.

HT-9 steel samples have been irradiated with fast neutrons (E > 0.1 MeV) to a low dose (1.2 × 10−3 dpa). Microstructure of the unirradiated and irradiated samples has been characterized by X-ray diffraction line profile analysis using different model-based approaches. The domain size and density of dislocations of the irradiated steel have been estimated. Different types of tensile tests have been carried out at room temperature to assess the changes in mechanical properties of HT-9 steel due to neutron irradiation.