The aim of this PhD project, co-sponsored by the UK Atomic Energy Authority (UKAEA)/Culham Centre for Fusion Energy (CCFE), is to contribute to understanding of degradation of Fe-Cr alloys and ferritic-martensitic steel (Eurofer steel) under radiation as it is invaluable for the development of fusion reactors, especially for the assessment of its structural integrity. This will be obtained by thoroughly considering the radiation induced microstructural changes that occur and how they relate to the mechanical properties.
This research is highly relevant to the UKAEA Irradiated Materials Experimental Testing and Research program and will also contribute to models of radiation defects and phase stability of fusion materials developed at UKAEA. The characterization of irradiation induced microstructure changes is usually carried out by TEM and APT, both of which have a limited capacity to gain statistically significant information from the bulk materials.
This work will focus on microstructural investigations with small angle scattering techniques based on neutrons or X-rays (SANS and SAXS, respectively), which are suitable for acquiring bulk-scale, statistically sound data on irradiation induced voids and precipitates. Radiation damage will be induced using the MC40 cyclotron (University of Birmingham) at different temperatures relevant for future fusion reactors and different dose levels. Protons with energies up to 14MeV will be used to mimic 14MeV neutron irradiation of fusion reactor environment. Irradiation with 14MeV protons will produce quasi-monotonic damaged layer with thickness of about 400um, significantly larger than the one often obtained and investigated after self-ion implantation (few micrometres). SANS and SAXS will be used as a primary method to map and quantify the shape and size distributions of voids and solid solution separation under irradiation. Advanced TEM and atomistic scale modelling will be used to correlate and help interpret the scattering results.
To form a complete story on the role of damage in the integrity of the materials, mechanical tests will be carried out on the irradiated samples at the Materials Research Facility so that we can establish the correlation between radiation damage and mechanical degradation. Within the project, micro- and nano-indentation at the Materials Research Facility will be used to determine the radiation induced hardening and small punch tests to estimate the ductility and fracture properties degradation of the irradiated samples.
A minimum 2.1 honours degree in materials science/engineering, metallurgy, physics, or chemistry. To apply, please provide your curriculum vitae and a cover letter to Dr Biao Cai, [Email Address Removed]