The influence of Mo on Suzuki-segregation-related microstructure evolution and mechanical properties of Co−Ni-based superalloy

Huakang Bian, Yujie Cui, Yunping Li, Akihiko Chiba, Yan Nie

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Mo, as one of the most important elements in superalloy, dramatically affected the microstructure and mechanical properties via solution strengthening, forming Mo-enriched phase, and atomic segregation (Suzuki effect). To verify the influence of Mo on the microstructure and mechanical properties of Ni–Co-based superalloy, two types of alloys containing 4 wt% (A4) and 8 wt% (A8) Mo were prepared. The microstructure was examined using X-ray diffraction, scanning electron microscope, and transmission electron microscope, while the mechanical properties were evaluated using tensile tests at both room temperature and elevated temperature (700 °C). The segregation of Mo at stacking faults was observed in both alloys after aging with pre-cold-rolling. At the same time, in alloy A8, direct precipitation of μ phase both along grain boundary and in the interior of matrix was observed after aging. In alloy A4, segregation of Mo along stacking fault ribbons resulted in formation of quasi-μ phase. The quasi-μ phase developed into μ phase during prolonged aging. There was no precipitate along grain boundary in A4 after aging resulting in poor ductility at both room and elevated temperature. The strength was enhanced by net effect of Suzuki segregation, γ′ phase strengthening, and fine μ phase.

Original languageEnglish
Pages (from-to)136-142
Number of pages7
JournalJournal of Alloys and Compounds
Volume768
DOIs
Publication statusPublished - 2018 Nov 5

Keywords

  • Co‒Ni-based superalloy
  • Mechanical property
  • Microstructure
  • Suzuki segregation

ASJC Scopus subject areas

  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys
  • Materials Chemistry

Fingerprint Dive into the research topics of 'The influence of Mo on Suzuki-segregation-related microstructure evolution and mechanical properties of Co−Ni-based superalloy'. Together they form a unique fingerprint.

  • Cite this