Science China Technological Sciences

, Volume 61, Issue 12, pp 1824–1828 | Cite as

Stability of γ′ multimodal microstructure in a Ni-based powder metallurgy superalloy

  • Ming Zhang
  • GuoQuan Liu
  • Hao WangEmail author
  • BenFu Hu


Multimodal size distribution of γ′ phase was obtained in a slow-cooling experiment following supersolvus solution treatment (1191°C). The morphology of the secondary γ′ particles exhibited splitting and protrusion instabilities. In the subsequent aging process (815°C), reverse coarsening was observed, i.e., the average precipitate size decreased with increasing aging time. Reverse coarsening slows the coarsening rate of the precipitates, increases the hardness of the alloy, and greatly improves the morphological stability of the γ′ phase.


Nickel alloys γ′ phase multimodal size distribution microstructure stability 


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© Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  1. 1.School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijingChina

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