New-Type Co-Based Superalloys Designed by CALPHAD Method

Abstract:

The phase equilibria of new-type Co-based superalloys which include the system of Co-Al-W were studied by CALPHAD method. It was shown that γ+γ' two-phase regions were existed in the calculated phase diagrams. The compositions of new-type Co-based superalloys which can obtain γ+γ' microstructures were predicted due to the calculated phase diagram. The mole fractions of the constituent phases of Co-Al-W-Ni-Cr alloys were calculated. The temperature of γ' phase began to precipitate at about 1050°C.

• Periodical: Materials Science Forum (Volume 816)
• Pages: 578-580
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.816.578
• Online since: April 2015
• Authors: Shu Yu Yang, Min Jiang, Lei Wang
• Keywords: Alloy Design, CALPHAD, New-Type Co-Based Superalloys, Thermodynamic Calculation

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