https://hdl.handle.net/11256/926 Phase Equilibria Data to supplement publications in JPED 2026-04-11T11:22:07Z https://hdl.handle.net/11256/943 Thermodynamic Description of the Ti-Al-O System Based on Experimental Data Ilatovskaia, Mariia; Savinykh, Galina; Fabrichnaya, Olga Phase equilibria of the TiO2-Al2O3 system were investigated experimentally using XRD, SEM/EDX and DTA methods. Temperature stability limits of the aluminum titanate (Al2TiO5) were detected. The thermodynamic parameters of the liquid phase as well as solid solution phases were assessed by CALPHAD approach using obtained experimental results. The thermodynamic data for the Ti-Al, Al-O and Ti-O systems and available experimental data for the Ti-Al-O system were critically evaluated and optimized to develop database of the Ti-Al-O system. 2017-06-08T00:00:00Z https://hdl.handle.net/11256/935 Experimental Investigation and Thermodynamic Modeling of the Co-Rich Region in the Co-Al-Ni-W Quaternary System Zhu, Jun; Titus, Michael S; Pollock, Tresa M The stabilities of the γ-(Co), γ′-Co3(Al,W), μ-Co7W6, β-CoAl and α-(W) phases in the Co-Al-W and Ni-Al-W ternary systems were investigated at 900, 1000, 1100 and 1300 °C. Electron probe microanalysis was used to determine compositions of the phases. Scanning electron microscopy was used to determine area fractions of the phases present after heat treatments. Thermodynamic modeling of the Co-Al-Ni-W quaternary system, using Pandat software, was incorporated to determine relevant thermodynamic parameters for phases in the Co-rich region of the system. Phases were modeled using the substitutional solution model and compound energy formalism. Excellent agreement was found between experiments and thermodynamic modeling. This new thermodynamic database enables predictions of stable γ-γ′ compositions for a new class of high temperature, high strength Co-base superalloys. 2017-03-20T00:00:00Z https://hdl.handle.net/11256/718 Thermodynamic assessment of the Co-Mo system A. Davydov; U. R. Kattner Experimental thermochemical and phase diagram data for the Co-Mo system were assessed. A consistent thermodynamic description, using a Redlich-Kister model for the solution phases and sublattice and line-compound models for the intermetallics, was obtained, and it agreed well with the critically evaluated experimental data. Several variations of the sublattice model for the and phases were compared with the traditional models used for these phases in other systems. Measured data indicate an abrupt decrease of the terminal Mo solubility in the fcc (Co) phase with decreasing temperature. This behavior was reproduced well by inclusion of the magnetic contribution to the Gibbs energy of the fcc phase. Addition of the magnetic term also led to the prediction of a fcc (Co) miscibility gap, and a high-temperature stability region of the paramagnetic cph (Co) phase. https://hdl.handle.net/11256/96 Al-Co-W 900C Phase Equilibria Data Lass, Eric; Maureen E. Williams; Carelyn E. Campbell; Kil-Won Moon; Ursula R. Kattner Phase equilibria at 900 °C in the Co-rich Co-Al-W ternary system are investigated through isothermal annealing of six alloy compositions for times up to 8000 h. The volume fraction of the L12-γ′ phase co-existing with disordered FCC-γ, B2 and D019 phases is found to steadily decrease with increasing annealing time indicating that it is unstable at 900 °C. Additional heat treatments at 850 and 1000 °C further suggest it is a nonequilibrium phase at all temperatures in the ternary system. The L12-γ′ phase dissolves slowly with significant amounts remaining in some alloys after 8000 h at 900 °C. However, the present work clearly indicates the microstructure is moving toward a three-phase equilibrium between γ, D019, and B2. The collected compositional and phase equilibria information provide much needed data for improving the available thermodynamic assessments of the ternary Co-Al-W alloy system. 2014-09-03T00:00:00Z