Control of precipitation behaviour of Hastelloy-X through grain boundary engineering. Issue 17 (22nd November 2017)

• Record Type: Journal Article
• Authors: Wang, Xiaoyan; Kurosawa, Kentaro; Huang, Ming; Lu, Xianke; Zhang, Dao; Kokawa, Hiroyuki; Yan, Yinbiao; Yang, Sen
• Is Part Of: Materials science and technology. Volume 33:Issue 17(2017)
• Page Start: 2078
• Page End: 2085
• Publication Date: 2017-11-22
• Subjects: Nickel-based superalloy -- aging -- precipitation -- Mo enrichment -- grain boundary character distribution -- thermal stability; Materials science -- Periodicals; Microstructure -- Periodicals; Metallurgy -- Periodicals; 620.1105
• DOI: 10.1080/02670836.2017.1345823
• Languages: English
• ISSNs: 0267-0836

Abstract

ABSTRACT: Grain boundary engineering (GBE) was employed to control the precipitation behaviour of Hastelloy-X alloy. The precipitate characteristics and thermal stability of grain boundary character distribution (GBCD) were investigated by aging at 850°C. M6 C carbides and µ phases were observed in the matrix and on grain boundaries, respectively. It revealed that the formation of µ phase was closely related to the grain boundary structure. GBCD effectively suppressed the nucleation and coarsening of µ phases on the grain boundaries. Owing to the Mo depletion in the vicinity of random grain boundary, the formation of the precipitates was inhibited on the adjacent grain boundaries. The thermal stability of the GBE-optimised microstructure was confirmed at 850°C for 720 h without significant microstructural degradation.