My first degree was in Materials Science at St Anne’s College Oxford, where I won the Morgan Advanced Ceramics Prize for practical work and Ironmongers prize for my final year thesis on titanium alloys. This was followed by a DPhil at Corpus Christi, Oxford developing novel methods for measuring micromechanical properties in copper and nickel alloys. During my doctoral studies I was a senior scholar at Corpus, as well as being the MCR social secretary and treasurer, playing lacrosse for the university, rowing for the college and meeting my now wife.
In 2009 I was awarded the Culham Centre for Fusion Energy Junior Research fellowship at St Edmund Hall. This fellowship allowed me to apply micromechanical testing methods developed in my doctoral studies to materials for fusion power – in particular irradiated tungsten alloys where I showed that implantation of helium can significantly alter mechanical behaviour of tungsten. In 2013 I was awarded a 5 year Royal Academy of Engineering Research Fellowship titled “Micro-engineering advanced alloys for extreme nuclear power environments”. This has been particularly focused on developing methods of measuring mechanical behaviour of materials at the nanoscale at temperatures up to 1000oC.
Research and Teaching
My research interests lie around the mechanical and physical behaviour of materials which operate under extreme conditions. These can include high temperatures such as those found in jet engines or nuclear reactors, high levels of radiation damage in fusion or fission reactors, and high stresses in structural and geological materials. By understanding materials’ behaviour and failure mechanisms under these conditions I work to develop new materials with better performance. This research is often in collaboration with leading international engineering companies and laboratories including Rolls Royce, UKAEA-CCFE, General Atomics, MicroMaterials and NNL. Currently I sit on the UKAEA Materials Research Facility advisory board and the management board of the Science and Technology of Nuclear Fusion Centre for Doctoral Training.
In 2015 I was awarded the Institute of Materials Minerals and Mining Grunfeld Memorial Award & Medal, for a professional contribution that has had significant influence on engineering applications in the metallurgical industries.
I teach a range of courses across the first two years of the materials science degree, mostly focused on mechanical behaviour of materials, microstructural evolution, and engineering applications of metals and ceramics. In the third year I teach an option course on Advanced Engineering Alloys and Composites. I also teach a range of graduate student courses for the Fusion CDT on nuclear materials and technology. I typically supervise one or two final year undergraduate projects a year as well as having a large number of doctoral students.
- Correcting for contact area changes in nanoindentation using surface acoustic waves CE Beck, F Hofmann, JK Eliason, AA Maznev, KA Nelson, DEJ Armstrong Scripta Materialia 128, 83-86
- Ion-irradiation induced clustering in W-Re-Ta, W-Re and W-Ta alloys: An atom probe tomography and nanoindentation study Alan Xu, David EJ Armstrong, Christian Beck, Michael P Moody, George DW Smith, Paul AJ Bagot, Steve G Roberts Acta Materialia 124, 71-78 (2017)
- Bend Testing of Silicon Microcantilevers from 21°C to 770°C D.E.J Armstrong, E. Tarleton, JOM 67 (12), 2914-2920
- Small-Scale Characterisation of Irradiated Nuclear Materials: Part II Nanoindentation and micro-cantilever testing of Ion Irradiated Nuclear Materials D.E.J. Armstrong, C.D Hardie, J. Gibson, A.J. Busby, P.Edmondson, S.G. Roberts Journal Nuclear Materials 462, 374–381 (2015)
- Ion-irradiation induced clustering in a W-Re-Os alloy: An Atom Probe Tomography and Nanoindentation study Alan Xu, Christian Beck, David E.J. Armstrong, Krishna Rajan, Paul A.J. Bagot, Steve G. Roberts – Acta Materialia Volume 87, April 2015, Pages 121–127
- High Temperature Indentation of Helium-Implanted Tungsten James S.K-L. Gibson, Steve G. Roberts, David. E.J. Armstrong Submitted Materials Science and Engineering A Materials Science and Engineering: A Volume 625, February 2015, Pages 380–384
- How oxidized grain boundaries fail H Dugdale, DEJ Armstrong, E Tarleton, SG Roberts, S Lozano-Perez Acta Materialia 61 (13), 4707-4713
- *Effects of sequential tungsten and helium ion implantation on nano-indentation hardness of tungsten DEJ Armstrong, PD Edmondson, SG Roberts Applied Physics Letters 102 (25), 251901
- Hardening of Self Ion Implanted Tungsten and Tungsten 5-wt% Rhenium, D.E.J Armstrong, X. Yi, E. Marquis, S.G. Roberts, Journal Nuclear Materials, (2013), Vol. 432, pp 428-436