After my first degree (in Natural Sciences) and my PhD in physical metallurgy, both at Cambridge University, I was appointed as Research Fellow in the Dept of Materials, University of Oxford, working in three separate subject areas over the course of twelve years: high voltage electron diffraction, stress corrosion cracking of Inconel and high temperature oxidation of stainless steel. I then worked as a technical writer and editor at the Energy Technology Support Unit, Harwell, for a while before joining the Open University, full-time, as a staff tutor in the Technology Faculty, based in Newcastle, in 1996. In this role I managed up to eighty associate lecturers teaching on our faculty's courses all over the NorthEast of England, Cumbria and continental Western Europe. In 2001 I transferred back to Oxford to perform a similar role. In 2006 I re-started research by spending a few months as an academic visitor at the University of Oxford, Dept of Materials and since then I have combined research in the Materials Engineering group of the Open University with the staff tutor role and latterly that of postgraduate tutor in the Department of Engineering and Innovation, Faculty of Mathematics, Computing and Technology. I retired as a staff tutor in December 2015 but remain active in research as a Visiting Fellow.
I am married to another metallurgist who's also an archaeologist and we conduct some joint research on archaeological materials particularly silver and copper.
My background is in using electron microscopy (both SEM and TEM) to study the structure and properties of grain boundaries (GBs) in metals, growth of grain boundary precipitates and the initiation of phase transformations at GBs. Along the way I’ve also worked on theoretical electron diffraction and stress corrosion cracking.
More recently I’ve also become interested in creep of high temperature materials and especially how electron backscattered diffraction (EBSD) can be used to investigate creep damage and to characterise the deformation structures developed during creep.
Although widely used to study engineering materials, EBSD has been used very little in studying archaeological metalwork and I have been using EBSD to examine gold, silver, copper and bronze objects from a range of periods between 13th century BC and 18th century AD to investigate their methods of manufacture. This technique has proved especialy useful in examining copper bolts from the hulls of ships of the time of Nelson's navy and we are comparing measurements of their crystallographic texture by neutron diffraction with the results of EBSD studies.
I'm still very interested in phase transformations and, in addition to work on how precipitation during service can affect the behaviour and lifetime of engineering components used at high temperature, have been looking at the mechanisms of discontinuous precipitation in silver-copper alloys and on the question of whether there might be a microstructural 'fingerprint' to distinguish unambiguously between either cast or wrought 'silver' from the modern era and objects that are genuinely old.
|Materials Engineering Group||Group||Faculty of Mathematics, Computing and Technology|
|Role||Start date||End date||Funding source|
This proposal aims to study electropulse-induced microstructure regeneration of stainless steels. Specifically, multi-scale modelling and lab-scale experiments will investigate the stability and reversibility of aged microstructures under pulsed electric currents, in cast austenitic stainless steel (CASS) and duplex stainless steel (DSS). In CASS, ageing produces precipitates. In DSS ageing induces spinodal decomposition and G-phase formation. Electropulsing’s ability to dissolve precipitates and reverse spinodal decomposition shows the potential to regenerate the microstructure and properties of alloys. This research is set to explore the mechanism behind this, to understand the scientific nature of the phenomena, and to assess the applicability of the technique in engineering practice.