Nano-twinning in a γ′ precipitate strengthened Ni-based superalloy. Issue 12 (2nd December 2018)

• Record Type: Journal Article
• Authors: Yuan, S. Y.; Jiang, Z. H.; Liu, J. Z.; Tang, Y.; Zhang, Y.
• Is Part Of: Materials research letters. Volume 6:Issue 12(2018)
• Page Start: 683
• Page End: 688
• Publication Date: 2018-12-02
• Subjects: Ni-based superalloy -- stacking faults -- twinning -- atomistic simulations; Materials science -- Research -- Periodicals; Biomedical materials -- Research -- Periodicals; Composite materials -- Research -- Periodicals; Biomedical materials -- Research; Composite materials -- Research; Materials science -- Research; Periodicals; 620.1105
• DOI: 10.1080/21663831.2018.1538021
• Languages: English
• ISSNs: 2166-3831

Abstract

ABSTRACT: Twinning has been found to be a dominate mechanism in the γ′ precipitate strengthened Ni-based superalloys during service at intermediate temperatures. Here, high-resolution transmission electron microscopy and atomistic simulations have been combined to show that the twin nucleation process can be facilitated by Co replacing a fraction of Al in the γ′ precipitates, due to the negative binding energy of Co–Co atoms. The study further reveals that the presence of Co promotes a new twinning pathway featured with nucleation of one complex stacking fault (CSF) on the middle plane in between two separated CSFs. GRAPHICAL ABSTRACT: IMPACT STATEMENT: We demonstrate that Co in the γ′ precipitates promotes a new twinning pathway featured with nucleation of one CSF on the middle plane between two separated CSFs.