26/3/14: JANNuS in-situ TEM irradiation & annealing experiments approved
An application to the EMIR panel for 5 days of microscope and beam time at the JANNuS Orsay facility to perform in-situ He+ and W+ irradiation TEM of tungsten at high temperatures has been approved as "A+ priority". Congratulations to Francesco Ferroni, Philip Edmondson and Xiaoou Yi for putting together an excellent proposal.
25/3/14: Workshop on Zirconium for Nuclear Applications
The MFFP group is organising a three-day workshop in Oxford on Zirconium for Nuclear Applications, 29 September to 1st October 2014.
The meeting will be centred on about a dozen keynote lectures (50 minutes) and two substantial poster sessions where "work in progress" will be reported. The meeting will be low cost (£400 all-inclusive), so as to encourage participation from active research students and postdocs.
Registration is now open. For further information, see here.
There was a strong presence from the MFFP group at the CNRS Gradschool "Solid Mechanics for Nanoscientists": Katie Plummer, Helen Pratt, Bo-Shuan Li and Luke Hewitt all attended. "There have been some amazing novel techniques spoken about..."
6/3/14: "Nellie" lives again
One of the group's most vintage pieces of equipment, our high-temperature microhardness tester (commissioned 1986), has been revived and is being used for testing tungsten and molybdenum. Up to 800°C so far, but the machine is in principle capable of 1500°C, so there will be more to come.
27/1/14: Vacancy: Postdoctoral research assistant in micromechanical testing of nuclear materials
Applications are invited for a postdoctoral position in micromechanical testing of nuclear materials, to investigate the utility of ion irradiation as a proxy for neutron irradiation in the study of the effects of radiation damage on the structure and properties of nuclear materials. For further details see here; but applications for this vacancy closed on 20/2/14.
2/12/13: Visit to KIT
Steve, Dave and James recently visited our collaborators at Karlsruhe Institute of Technology in Germany. This is them touring the hot cells where work on our neutron irradiated tungsten is being performed.
11/11/13: MFFP research at the APS
David Collins and Ed Tarleton are working at the Advanced Photon Source, Argonne National Laboratory this week. They sent us a picture.
18/10/13: Group photo
Quite a few people couldn't make it - but I think we still have 49 in the picture, taken after the Friday group meeting.
07/10/13: New academic year, new arrivals
Welcome to our new graduate research students in various aspects of "Materials for Fusion and Fission Power": Bo-Shiuan Li, Yeli Guma, Helen Pratt, Luke Hewitt, Selim Barhli, Junnan Jiang, Alasdair Morrison, and James Sayers.
28/9/13: Two Fellowships in Nuclear Materials
Congratulations to Phil Edmondson and Dave Armstrong for their recently announced fellowship awards. Phil won a 5-year EPSRC Nuclear Fellowship to study Fundamentals of the Behaviour of Fission Products in Oxide Nuclear Fuels and Dave a 5-year Royal Academy of Engineering fellowship on Micro-Engineering Advanced Alloys for Extreme Nuclear Power Environments.
06/09/13: MFFP student in final 3 for SET award.
Luke Hanna, who did his final year ("Part 2") project on atom-probe tomography of tungsten-tantalum alloys, is in the final three for this year's UK SET award in materials. The winner was decided on 26th September; unfortunately Luke didn't get the prize; but being in the national top three is still very good!
04/09/13: New paper on ODS alloys
An in-situ powder neutron diffraction study of nano-precipitate formation during processing of oxide-dispersion-strengthened ferritic steels, H. Zhang, M.J. Gorley, K.B. Chong, M.E. Fitzpatrick, S.G. Roberts, P.S. Grant: J. Alloys & Compounds, in press, 2013: DOI: 10.1016/j.jallcom.2013.08.069
The evolution of phases in a Fe-14Cr-10Y2O3 (wt.%) oxide-dispersion-strengthened ferritic steel during mechanical alloying (MA) and subsequent annealing was studied by high resolution powder neutron diffraction, with emphasis on the kinetics of oxide-based nanoprecipitate formation. Y2O3 particles were completely dissolved into the ferritic matrix during MA. The formation of nano-precipitates was then observed by in-situ thermo-diffraction experiments during annealing of as-milled powder above 900°C, supported by scanning electron microscopy. This revealed nano-precipitate coarsening with increasing annealing temperature. Powder microhardness was measured at various processing stages, and hardness changes are discussed in terms of the measured phase fractions, crystallite size and lattice strain at different temperatures and times.
02/09/13: September workshops: "Tungsten" and "Modelling"
Two workshops will be run this year, in the week 23-27 September:
- Tungsten for Nuclear Applications.
23-25 September. Workshop timetable now available.
- Modelling of Radiation Damage in Materials.
25-27 September. Workshop timetable now available.
Registration fees are now "late registrations" at £50 higher cost. But the workshops are still good value...
27/6/13: New Paper: Effects of sequential tungsten and helium ion implantation on nano-indentation hardness of tungsten
In this paper the dramatic effect that helium implantation can have on the nano-hardness of tungsten is investigated using nanoindentation. This has much relevance to the use of tungsten for plasma facing components in tokamaks. The full paper is here
13/6/13: Ele Grieveson wins prize.
Ele Grieveson (3rd year D.Phil. student) has won "Best Student Paper" for her poster on "Investigation into irradition effects in ODS-alloys using ion implantation and micromechanical testing" at the 2013 IEEE 25th Symposium on Fusion Engineering, San Francisco.
3/6/13: New paper: How oxidised grain boundaries fail.
In this paper, through a multifaceted approach using micromechanical testing, analytical TEM and modelling, we show that individual grain boundaries, selectively oxidized after exposure to simulated pressurized nuclear reactor cooling water, can be mechanically tested so that their resistance to fracture can be quantified. For further details see here.
22/4/13: New paper: Effects of irradiation temperature and dose rate on the mechanical properties of self-ion implanted Fe and Fe-Cr alloys
This paper documents very strong dose rate effects on the hardening produced in FeCr alloys by ion-implantions. It appears that the strong hardening seen at low dose rates is due to chromium segregation to the dislocation loops produced by the radiation damage. For further details see here.
05/1/13: Review Paper Published
A large review paper which we have contributed to has just been published in the Journal of Nuclear Materials. This paper summarises work carried out on tungsten for fusion applications across Europe under the EFDA-W project. James Gibson, David Armstrong and Steve Roberts contributed to the work on fracture at the macro and micro-scale of tungsten and tungsten-tantalum alloys. The full paper is online here.