Exploration of High Entropy Alloys for Turbine Applications

Under this SBIR program, QuesTek Innovations LLC will explore the possibility of high entropy alloy (HEA) for industrial gas turbine (IGT) components with its computational alloy design tools and methods. QuesTek is uniquely qualified to find HEAs suitable for turbine components with extensive experience in superalloy design and the rapid development of materials models and databases. Phase I efforts focused on finding HEA compositions that exhibit suitable phase equilibria for blade applications, culminating in the construction and validation of a large CALPHAD (CALculation of PHAse Diagrams) thermodynamic database specifically designed for HEA compositions, as current CALPHAD databases are not sufficiently accurate at equiatomic compositions. Such CALPHAD databases are an essential component of any materials design effort and will offer quantitative predictions of phase stability. The proposed Phase II will consist of using QuesTek’s Integrated Computational Materials Engineering (ICME) technologies to develop several HEA blade design concepts. Focus will be placed on optimizing creep, strength, and oxidation performance, made possible by the development of quantitative structure-property models and highperformance computing resources. The performance of intermediate-scale (~10-30 lbs) prototype castings on the above properties will be assessed and compared to benchmark alloys, demonstrating the potential of HEAs for IGT applications. This alloy development program will include several partners: Siemens Power Generation, a leading manufacturer of land-based gas turbines for power plants; Carpenter Technology and H.C. Starck, global leaders in transition metal and refractory alloy production; and Prof. Peter K. Liaw of the University of Tennessee, a world-renowned expert in HEA science. The potent partnership of a materials designer (QuesTek), a top HEA expert (Peter Liaw), alloy producers (Carpenter and H.C. Starck), and an OEM gas turbine manufacturer (Siemens), ensures a successful program for accelerating the development of the currently nascent HEA technology towards a superior commercial product.