1. Low temperature study of phase equilibria in the Co–Ni–W ternary system: Evidence of a new intermetallic phase Co3W-D0a
- Author
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Jérôme Andrieux, Rafael Cury, Olivier Dezellus, Nicolas Bouliez, Rodica Chiriac, Sophie Cazottes, B. Gardiola, Florence Robaut, Jean-Claude Crivello, François Toche, Laboratoire des Multimatériaux et Interfaces (LMI), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut de Chimie et des Matériaux Paris-Est (ICMPE), Institut de Chimie du CNRS (INC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Matériaux, ingénierie et science [Villeurbanne] (MATEIS), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS), Science et Ingénierie des Matériaux et Procédés (SIMaP), Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), and Université Grenoble Alpes (UGA)
- Subjects
010302 applied physics ,Materials science ,Ternary numeral system ,Mechanical Engineering ,Metals and Alloys ,Intermetallic ,Thermodynamics ,Sintering ,chemistry.chemical_element ,02 engineering and technology ,[CHIM.MATE]Chemical Sciences/Material chemistry ,Tungsten ,021001 nanoscience & nanotechnology ,01 natural sciences ,Isothermal process ,chemistry ,Mechanics of Materials ,Phase (matter) ,Powder metallurgy ,0103 physical sciences ,Materials Chemistry ,0210 nano-technology ,Ternary operation ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience; Tungsten heavy alloys (Co-Ni-W) of different compositions were prepared by powder metallurgy (solid sintering), heat treated at 800°C and 1000°C and subsequently analyzed. The experimental phase identifications and composition measurements emphasized discrepancies compared to the isothermal ternary sections simulated with commercial thermodynamic databases. The isothermal sections at 800°C and 1000°C were found more complex than expected since a new intermetallic phase appeared to be stable (D0a structure-Cu3Ti prototype). Likewise, an interpretation of phase equilibria evolution with temperature was established to reach agreement with high temperature data. Formation enthalpies associated with the new phase were obtained through first-principles calculations and supported experimental results as they confirmed the stabilizing role of Ni addition for the D0a structure.
- Published
- 2022