Latest Papers

A discrete dislocation plasticity study of the micro-cantilever size effect
E Tarleton, DS Balint, J Gong, and AJ Wilkinson
Acta Materialia (2015) vol. 88, 271-282
doi:10.1016/j.actamat.2015.01.030


Measurement of probability distributions for internal stresses in dislocated crystals
AJ Wilkinson, E Tarleton, A Vilalta-Clemente, J Jiang, TB Britton, and DM Collins
Applied Physics Letters (2014) vol. 105, 181907
doi:10.1063/1.4901219


〈c + a〉 Dislocations in deformed Ti–6Al–4V micro-cantilevers
R Ding, J Gong, AJ Wilkinson, IP Jones
Acta Materialia (2014) vol. 76 127-134
doi:10.1016/j.actamat.2014.05.010


Slip band–grain boundary interactions in commercial-purity titanium
Y Guo, TB Britton and AJ Wilkinson
Acta Materialia (2014) vol. 76 1-12
doi:10.1016/j.actamat.2014.05.015


Simulation of deformation twins and their interactions with cracks
A Stoll and AJ Wilkinson
Computational Materials Science (2014) vol. 89 224-232
doi:10.1016/j.commatsci.2014.03.041


In-service materials support for safety critical applications – a case study of a high strength Ti-alloy using advanced experimental and modelling techniques
D Rugg, TB Britton, J Gong, AJ Wilkinson, PAJ Bagot
Materials Science and Engineering A (2014), vol. 599 166-173
doi:10.1016/j.msea.2014.01.031


News

Dislocation Dynamics embedded in FEA
Ed Tarleton in collaboration with Daniel Balint (Imperial College) have successfully embedded discrete dislocation dynamics simulations of plasticity within a finite element analysis framework that handles complex displacement and traction boundary conditions. This new modelling capability is an important tool for analysis of small scale mechanical testing experiments. Micro-cantilever bend tests on hexagonal Ti and Zr crystals conducted by Jicheng Gong have been simulated. The marked size effect, stochastic flow behaviour, and slip band spacing evident in the experiments are all well captured by the simulations. The study is reported in Acta Materialia

DDD-FEA modelling
slip band-GB interaction

DPhil Studentships Available
There are two funded DPhil projects available within the group for October 2015 start. Both concern micromechanical aspects of deformation and fatigue in Ti alloys. The first concentrates on continuing developent and application of small-scale ultrasonic testing for high cycle fatigue. The other will continue a successful vein of work using HR-EBSD and other methods to study slip band – grain boundary interactions. Both projects will involve collaboration with Rolls Royce and link into activiities on the HexMat Programme grant. Unfortunately funding is restricted to UK and EU citizens.
'Further Details'


Microscopy and Analysis cover

Microscopy and Analysis cover
Sample preparation of zirconium alloys for EBSD can be difficult and lack reproducibility. Hamid Abdolvand has been working with a broad ion beam based system, the Precision Etching and Coating System II (PECS II) from Gatan. With help from friends at Gatan he has been able to produce samples that generate high quality EBSD patterns reproducibly over large areas. An example map taken from a highly deformed Zircaloy-2 sample and containing many deformation twins was used as the front cover of the November issue of Microscopy and Analysis.

Meet us at

TMS 2015
TMS 2015
Orlando, FL 15-19 March 2015
- invited presentation from Hamid Abdolvand on hi-res EBSD and 3D-XRD, plus Yi Guo on slip-band grain boundary interactions and twinning in Ti


ICSMA 17
4th Int Conf on Material Modeling
Berkeley CA, 27–29 May 2015
- several members of the group will be presenting at the HexMat organised session on hexagonal metals


M and M 2015
EBSD 2015 - Annual RMS meeting
Glasgow, UK, 30-31 March 2015
- many members of the group will be attending and hopefully presenting talks and posters


EBSD 2015
Microscopy and Microanalysis 2015
Portland, OR, 2-6 August 2015
- presentations by Angus W on 'progress with EBSD strain mapping'


ICSMA 17
Int Conf on Strength of Materials 2015
Brno, Czech Republic, 9–14 August 2015
- several members of the group will be attending and hopefully presenting talks and posters