Alloying Element Ta Effect on Microstructure of Co-Al-W Superalloy by Vacuum Arc Melting

Abstract:

Co-based high temperature alloys have been widely used in aeronautics and astronautics industry, because of its high strength at high temperature, excellent resistance of hot corrosion and oxidation. Unlike the traditional Co-based superalloys, strengthened by solution and carbide strengthening, the novel Co-Al-W superalloys are strengthened by a ternary compound with the Ll₂ structure γ-Co₃(Al,W). And the novel Co-Al-W superalloys showing high-temperature strength greater than those of conventional nickel-base superalloys, will become the candidates for next-generation high-temperature materials. We research alloying element Ta effect on microstructure of Co-Al-W superalloys by vacuum arc melting. Compare with the microstructure before and after adding alloying element Ta of Co-Al-W superalloy, we find that most of Ta element distributed in the γ-Co substrate phase, stabilizing and reinforcement the γ phase.

• Periodical: Advanced Materials Research (Volumes 718-720)
• Pages: 10-13
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.718-720.10
• Online since: July 2013
• Authors: Wen Jun Zhao, Yang Tao Xu
• Keywords: Alloying Element Ta, Co-Al-W Superalloy, Microstructure, Vacuum Arc Melting

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