INVESTIGATION OF SUPERALLOY COMPOSITION SPACE USING HIGH THROUGHPUT THIN FILM SYNTHESIS AND SYNCHROTRON X-RAY DIFFRACTION

The development of new nickel-base superalloys, which commonly contain in excess of 10 alloying elements, is a challenge with nearly unparalleled complexity. The vast number of alloying element combinations and the amount of each element that can be added means that the efficient design of new alloys requires the use of computational techniques. However, the viability of the computationally designed alloys is founded upon the fidelity of the databases used to calculate the thermodynamic equilibrium phases. In this work, high-throughput physical vapor deposition has been used to assess the Ni-Cr-W and Ni-Cr-Co ternary systems. The synthesis of compositionally graded thin film samples has allowed a large area of composition space to be assessed and the use of synchrotron X-ray diffraction to analyze the thin film samples has provided a method of phase identification at a resolution beyond that achievable with laboratory-based techniques. The data acquired has allowed previously unknown phases in these ternary systems to be identified, the extent of the constituent phase fields to be determined and enabled the compositional dependence of the y lattice parameter to be obtained.