A special coarsening mechanism for intergranular helium bubbles upon heating: A combined experimental and numerical study

Jie Gao, Hefei Huang, Xiang Liu, Chengbin Wang, James F. Stubbins, Yan Li

Research output: Contribution to journalArticle

Abstract

Here, by using in situ transmission electron microcopy, we discovered a special mechanism governing the coarsening of intergranular helium bubbles, which exhibit pancake-like growth along grain boundaries to achieve coalescence with another bubble upon heating at 673 K. The developed analytical model, addressing the stress field induced by the bubble internal pressure, well reproduced the observed shape evolution during the bubble growth. Moreover, we show that the coalescing rate of intergranular bubbles was controlled by the surface diffusion and can be accelerated by the pressure gradient between bubbles.

Original languageEnglish (US)
Pages (from-to)93-97
Number of pages5
JournalScripta Materialia
Volume147
DOIs
StatePublished - Apr 1 2018

    Fingerprint

Keywords

  • Analytical modelling
  • Coarsening mechanism
  • In situ TEM heating
  • Intergranular helium bubbles

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering
  • Metals and Alloys

Cite this