title: The Different Roles of Entropy and Solubility in High Entropy Alloy Stability.
abstract: Multiprincipal element high entropy alloys stabilized as a single alloy phase represent a new material system with promising properties, such as high corrosion and creep resistance, sluggish diffusion, and high temperature tensile strength. However, the mechanism of stabilization to form single phase alloys is controversial. Early studies hypothesized that a large entropy of mixing was responsible for stabilizing the single phase; more recent work has proposed that the single-phase solid solution is the result of mutual solubility of the principal elements. Here, we demonstrate the first self-consistent study of the relative importance of these two proposed mechanisms. In situ high-throughput synchrotron diffraction studies were used to monitor the stability of the single phase alloy in thin-film (Al1-x-yCuxMoy)FeNiTiVZr composition spread samples. Our results indicate that a metastable solid solution can be captured via the rapid quenching typical of physical vapor deposition processes, but upon annealing the solid-solution phase stability is primarily governed by mutual miscibility.
authors: Department of Chemical Engineering, University of South Carolina , Columbia, South Carolina 29208, United States.|SmartState Center for the Strategic Approaches to the Generation of Electricity, University of South Carolina , Columbia, South Carolina 29208, United States.
authors: Benjamin
authors: B
authors: Ruiz-Yi
authors: Department of Chemical Engineering, University of South Carolina , Columbia, South Carolina 29208, United States.|SmartState Center for the Strategic Approaches to the Generation of Electricity, University of South Carolina , Columbia, South Carolina 29208, United States.
authors: Jonathan Kenneth
authors: JK
authors: Bunn
authors: Department of Materials Science and Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors: Drew
authors: D
authors: Stasak
authors: Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States.
authors: Apurva
authors: A
authors: Mehta
authors: Ames Laboratory, Iowa State University , Ames, Iowa 50011, United States.
authors: Matthew
authors: M
authors: Besser
authors: Ames Laboratory, Iowa State University , Ames, Iowa 50011, United States.
authors: Matthew J
authors: MJ
authors: Kramer
authors: Department of Materials Science and Engineering, University of Maryland , College Park, Maryland 20742, United States.
authors: Ichiro
authors: I
authors: Takeuchi
authors: Department of Chemical Engineering, University of South Carolina , Columbia, South Carolina 29208, United States.|SmartState Center for the Strategic Approaches to the Generation of Electricity, University of South Carolina , Columbia, South Carolina 29208, United States.
authors: Jason
authors: J
authors: Hattrick-Simpers
mesh_terms: D000497:Alloys / Q000737:chemistry*; D020650:Combinatorial Chemistry Techniques; D003343:Corrosion; D019277:Entropy; D008422:Materials Testing; D015394:Molecular Structure; D012995:Solubility; D013499:Surface Properties; D013696:Temperature
chemical_list: D000497:Alloys
keywords: alloys; entropy; metastable solid solution; mutual miscibility; solubility; stability