|About this Abstract
||1st World Congress on High Entropy Alloys (HEA 2019)
||High Entropy Alloys 2019
||Modeling and Experimental Validation of Refractory CCA Solidification and Homogenization
||David Smathers, Cameron McNamara, Marie Thomas, Chris Kantner
|On-Site Speaker (Planned)
A CALPHAD-informed Integrated Computational Materials Engineering (ICME) has been used to identify novel refractory Complex Complimentary Alloy (CCA) compositions of interest. However, the design and scale-up of these alloys is still a significant challenge, and practical production of CCAs towards a specific commercial product has yet to be demonstrated.
This paper describes results from an experimental program to evaluate their melting, solidification, and homogenization characteristics. Additionally, homogenization results are compared to simulation to assess the accuracy of predictive tools. Prototype 15 lb. ingots of 5 Nb-based CCA compositions identified using high throughput methods were vacuum arc melted, processed and evaluated to understand challenges associated with the scale-up of this class of alloy from button to lab ingot. In addition to characterizing the solidification behavior and as-cast microstructure, the impact of aluminum content on the various homogenization cycles was studied for each alloy and compared to DICTRA simulations.