Dynamic wetting behavior of molten Al on α-Al2O3 substrate during heating in high magnetic field

Abstract

The study observed the dynamic wetting behavior of molten Al on C-plane α-Al2O3 and R-plane α-Al2O3 substrates during heating under both 0 T and 6 T high magnetic fields (HMFs). Contact angles, contact (spreading) diameters, and heights were quantified using photographic data. The underlying mechanisms of dynamic wetting behavior under HMFs were analyzed, and dynamic wetting behavior models were developed. Under the 6 T HMF, the dynamic wetting behavior of molten Al on both oriented α-Al2O3 substrates underwent significant intensification, leading to distinctive changes in the molten Al's morphology. Upon reaching stability, molten Al exhibited significantly reduced contact angles and heights, along with a notable increase in spreading diameter under the 6 T HMF compared to the 0 T HMF. The dynamic wetting behavior was determined by the relative relationship between driving forces (resulting from changes in the three interfacial energies) and resistance (due to friction and hindrance caused by the surface oxide film of the molten Al during outward spreading). Consequently, two distinct dynamic wetting models were formulated for 0 T and 6 T HMFs. These findings open up novel possibilities for using HMFs to manipulate the wetting behavior of molten metals.