CDT Advanced Materials Characterisation

Taking Co/Ni superalloys into service

Supervisor	Professor David Dye
University	Imperial College London
Industry Co-Sponsor	Rolls-Royce
Project Description	New Co/Ni alloys the research team have recently patented show great promise for polycrystalline applications where traditional P/M 50% 𝛾′ Ni superalloys cannot be fabricated, e.g. where isothermal forgingroutes are impractical. Examples include thin section applications, where the low solvus temperatures alloy hot rolling, die forging and induction forging process routes, where dynamic recrystallisation allows very fine grain sizes (with improved strength and fatigue performance) to be achieved [eg Nicolaÿ et al., Acta Mater, 2019].
Key Techniques	(1) The primary technique will be EBSD characterisation and segmentation of deformed vs dynamically recrystallised grains, and the associated texture and grain-average misorientation analysis. (2) Mechanical characterisation via rolling and forging simulation in the Gleeble. (3) SEM characterisation of the 𝛾′ and grain boundary phase microstructures, their evolution and effect on the microstructure evolution during forming. (4) TKD and (S)TEM measurements using NBED-type modes to quantify the grain boundary and nanoscale oxide phases developed. There is the potential to complement these with APT analysis if required.
Note	Applicants for this project may be required to be eligible for security clearance to work on UK government programmes

For information on how to apply for this project please visit cdt-acm.org/phd-opportunities

Jennifer Hack
The CDT gave me the opportunity to meet people working in different fields and gain experience in a wide range of characterisation techniques that I could apply to my research.