Last week Dr Euan Wielewski travelled to cold and snowy Ithaca with PhD students Kayleigh Nelson and Chris Triantafyllou to carry out experiments at the Cornell High Energy Synchrotron Source (CHESS).
Following up on Kayleigh's previous work, her experiments focused on the material's behaviour during strain jumps and Chris' experiments compared the fatigue behaviour with and without dwell episodes. These experiments marked the start of investigations on unidirectionally-rolled Ti64 for Chris and on cross-rolled Ti64 for Kayleigh.
The huge advantage of working in-situ at a synchrotron is that we were able to capture lattice strains through powder (x-ray) diffraction with an acquisition frequency of up to 10Hz. This is not only useful in providing a deeper understanding of the mechanical response at the grain level, but also generates information that can be used to significantly improve our computational models. Both Kayleigh and Chris will be resuming work using FEpX later next year, also developed at Cornell University.
Many thanks go to our collaborators from CHESS, Darren Pagan and Peter Ko, as well as Glenhead Engineering for their fantastic work with our millimetre-thick specimens!