Congratulations to Tom Davis, an Oxford Fusion CDT student who successfully defended his thesis at viva in December 2020. Tom’s thesis is entitled “On nanosized precipitates in steels for advanced nuclear reactors” and his supervisors are Professor Armstrong, Professor Moody, Dr Bagot & Dr Auger. Well done Tom!
Now that his PhD is complete, Tom’s plans for the future are:
“Next for me is to focus on my company, Davis & Musgrove Ltd. We are an innovative engineering British company that is solving some of the major challenges in fusion and fission energy, and defence systems. In particular to fusion, commercialisation of this energy source requires unique engineering, technology, and regulatory solutions. Our company has patent-pending technologies which we are actively developing for commercialisation which solves some of the most difficult challenges in fusion energy – building the box”.
An abstract from Tom’s thesis is below.
“Nuclear fission power is a reliable and zero carbon dioxide emitting energy source and nuclear fusion is regarded as the ultimate terrestrial energy source. Both processes require radiation resistant structural reactor core materials. Atom probe tomography, nanoindentation, and electron microscopy were used to investigate a) radiation-induced precipitation of nanosized MnNiSi precipitates (MNSP) and nanosized copper-rich precipitates (CRP), and radiation-induced solute segregation to dislocations in neutron and ion irradiated T91 ferritic martensitic steel and b) the effect of yttrium-titanium-oxygen (Y-Ti-O) nanosize precipitates on the grain structure and mechanical properties of Fe-14Cr-W-0.25Ti-0.25Y2O3 (14YWT (wt%)) oxide dispersion strengthened steel. Two neutron irradiated T91 steel conditions were investigated: 2.14 dpa at 327C and 8.82 dpa at 377C. The MNSP compositions fell near the MnSi(Ni) phase field, which is distinctly different than the typically cited ‘Gphase’ (Mn6Ni16Si7). MNSPs appeared as a coprecipitated appendage to CRPs. CRP-MNSP number densities, radii, and volume fractions agreed well with literature cluster dynamics model. Parallels were drawn between the limited database on MNSPs in neutron irradiated FeCr alloy systems with the extensive literature on precipitate evolution in reactor pressure vessel steels. T91 was Fe4+ irradiated from 0.12 dpa to 4.1 dpa at ∼300C with the characterisation of MNSP and their impact on mechanical properties were discussed. 14YWT Y-Ti-O (7–15 nm diameter; number density 1023 − 1024 #/m3) particles had a small effect on the hardness, suggesting that the dominant hardening mechanism was related to the grain boundary refinement rather than the dislocation pinning on the oxides”.