Effects of gravity on the capillary flow of a molten metal

Yangyang Wu, Konstantinos Lazaridis, Mikhail D. Krivilyov, Sinisa Dj Mesarovic, Dusan P. Sekulic

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


Repair and construction in space by means of brazing requires understanding of the effect of gravity on the capillary flow of a molten metal. We perform two sets of experiments: (1) spreading of a sessile drop of liquid aluminum-silicon-flux (Al-Si-KxAlyFz) composite braze on a horizontal alumina (Al2O3) substrate (a non-wetting surface), and (2) capillary flow of the same braze alloy on an inclined aluminum-manganese (AA3003) substrate (a wetting surface). We vary the mass of the brazing liquid and the inclination of the substrate (i.e., the relative direction of gravity). In the composite metal/flux sessile drop experiments, we observe a secondary liquid flux meniscus forming at the contact line between the liquid Al-Si and the alumina substrate. We demonstrate that the equilibrium contact angle appears to be close to 180°, while the apparent contact angle depends on the mass of the braze. In the second set of experiments, we study the molten braze alloy on different inclinations of AA3003 in a wedge-T wetting/non-wetting assembly. As the inclination angle decreases, the wetting distance increases and the surface profile changes from a non-symmetric bag-like shape to a more symmetric pancake shape. With the mass decreasing, the surface profile on the vertical substrate approaches a symmetric shape when the wetting distance is equal or smaller than the capillary length. While the non-homogeneous melting and hence, the non-homogeneous microstructure of the melt, may prevent a full symmetry. Computational predictions of equilibrium shapes are in good agreement with experimental results.

Original languageEnglish
Article number130400
JournalColloids and Surfaces A: Physicochemical and Engineering Aspects
StatePublished - Jan 5 2023

Bibliographical note

Publisher Copyright:
© 2022 Elsevier B.V.


  • Brazing
  • Contact angle
  • Energy minimization
  • Non-wetting
  • Wetting

ASJC Scopus subject areas

  • Surfaces and Interfaces
  • Physical and Theoretical Chemistry
  • Colloid and Surface Chemistry


Dive into the research topics of 'Effects of gravity on the capillary flow of a molten metal'. Together they form a unique fingerprint.

Cite this