|About this Abstract
||2017 TMS Annual Meeting & Exhibition
||Gamma (FCC)/Gamma-Prime (L12) Co-Based Superalloys II
||Elemental Partitioning Behaviour in Ni-Co-Al-Ti-Cr Alloys
||Sioned C. H. Llewelyn, Katerina Christofidou, Vicente Araullo-Peters, Nick Jones, Emmanuelle Marquis, Mark Hardy, Howard Stone
|On-Site Speaker (Planned)
||Sioned C. H. Llewelyn
The relative concentrations of alloying elements in Ni-based superalloys have a marked effect on elemental partitioning behaviour within the principally γ-γ' microstructure, thus determining the properties conferred by the alloying additions. A recently developed class of high Co-Ti superalloys, exhibiting superior high temperature strength over conventional superalloys, contradicts established theory regarding the effects of alloying with Co. An improved understanding of the phase equilibria in such alloys is critical if optimised compositions are to be designed. This study uses three-dimensional atom-probe tomography to examine the effects of varying the Ni:Co ratio on elemental partitioning in alloys based on the Ni-Co-Al-Ti-Cr system at 800°C. In addition, phase compositions are correlated with those obtained using thermodynamic modelling to determine the extent to which computational tools can reliably guide future alloy design. This work was supported by Rolls-Royce plc, the EPSRC under EP/H022309/1 and EP/M005607/1 and the University of Michigan College of Engineering.