Experimental investigation and thermodynamic assessment of the Al-Co-Ni system |
| |
| Affiliation: | 1. Center for Hierarchical Materials Design (CHiMaD), Northwestern University, 2205 Tech Drive, Evanston, IL 60208, United States;2. Materials Science and Engineering Division, National Institute of Standards and Technology, 100 Bureau Dr., MS 8555, Gaithersburg, MD 20899, United States;3. Department of Mechanical Engineering and Materials Science, University of Pittsburgh, 3700 O′Hara Street, Pittsburgh, PA 15261, United States;4. Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, United States;1. State Key Laboratory of Powder Metallurgy, Central South University, Hunan 410083, PR China;2. Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing 100083, PR China;3. College of Metallurgy and Materials Engineering, Hunan University of Technology, Zhuzhou 412007, China;4. College of Mechanical and Electrical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China;5. MSI, Materials Science International Services GmbH, Am Wallgraben 100, 70565 Stuttgart, Germany;1. State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083, PR China;2. Department of Materials Science and Engineering, The Ohio State University, 2041 College Road, Columbus, OH 43210, USA;3. School of Energy Science and Engineering, Central South University, Changsha, Hunan 410083, PR China;4. School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083, PR China |
| |
| Abstract: | The Al-Co-Ni system is essential to both Co- and Ni-based superalloys. In this study phase relationships among A1, L12 and B2 at 800 °C have been investigated by using equilibrated alloys. Four samples were prepared and annealed at 800 °C for 14 days. SEM-EDXS and XRD were used to analyze the annealed samples. The results indicated that two-phase L12+B2 and three-phase A1+L12+B2 regions exit.A thermodynamic reassessment of the entire Al-Co-Ni system has been made according to the CALPHAD method. Compared to the previous assessments, more recent experimental results have been considered. In the Al-Co binary system, the phase named Y-Co4Al13 has been added on the basis of the available literature. The order-disorder model has been adopted to describe the A1/L12 and A2/B2 phase relations, respectively. Three ternary compounds in the Al-rich region have been introduced. Three-sublattice model has been selected to describe the τ1 phase with a considerable solubility extension. Thermodynamic interaction parameters have been optimized, considering the available experimental data. In this work several diagrams were calculated, which can fit experimental results in the whole composition range. A satisfactory agreement was obtained. As a result phase equilibria in the interested ferromagnetic shape memory alloys are calculated. |
| |
| Keywords: | Calphad Thermodynamic modeling Phase equilibria Superalloys |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
