Partition Behavior of Ni between γ and γ' Phases in the New Type Co-Based Superalloys

Abstract:

The phase equilibria of Co-Al-W-30Ni-2Cr (at. %) alloy was established at both 900 °C and 1000 °C. The partition coefficients of Ni between the γ and γ' phases of Co-Al-W-Ni-2Cr alloys with different Ni contents were calculated at 1000 °C. The partition coefficient increased with increasing Ni content when the Al/W ratio was fixed. The maximum values of the partition coefficient was achieved at the Al/W ratio of 2.8 when the Ni content are 20, 30 and 40 at. %, respectively. The precipitation behavior of γ' phase in the Co-Al-W-30Ni-2Cr alloys with the Al/W ratio 2.8 was also investigated. The γ' phase began to precipitate at 1160 °C.

• Periodical: Materials Science Forum (Volume 849)
• Pages: 488-491
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.849.488
• Online since: March 2016
• Authors: Shu Yu Yang, Shuang Hong Wang
• Keywords: Alloying Strengthening, Co-Based Superalloys, Partition Behavior, γ' Phase

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