The properties of solid-liquid interfaces (SLIs) govern a wide variety of processes of technological import, e.g., wetting, heterogeneous nucleation, casting, and crystal morphology and growth. We examined the chemically heterogeneous Al-Pb SLI to determine how interfacial structure and dynamics affect phenomena of experimental interest. Transmission electron microscopy experiments show that liquid Pb inclusions undergo Brownian motion within a solid Al matrix, using molecular-dynamics simulations as well as the characterization methodology explicitly developed for the Al-Pb SLIs, we found Al-Pb solid-liquid interfaces [Phys. Rev. Lett, 110, 096102 (2013)] exhibit premelting transition below the melting point of Al. I will present in this talk: i) the roles played by Al diffusion and the interfacial premelting phase transition at the solid-liquid interfaces in the phenomenon (Brownian motion of Pb inclusion within the Al matrix). ii) The spreading kinetics of Pb droplets on Al substrate, the effect of this premelting on the droplet spreading kinetics, and effect of premelting on the droplet equilibrium contact angle. iii) Some preliminary results on the interactions between the Al crystal-melt interfaces and the liquid phase Pb inclusions during the rapid solidification.

Yang Yang received his Ph.D. from the East China Normal University, in 2010. He subsequently joined Prof. Xingao Gong’s research group at Fudan University, where he was a research assistant. From 2011 to 2013, he worked with Prof. Brian Laird at University of Kansas as a postdoc. From 2013 to 2014, he worked with Prof. Mark Asta as a postdoc at University of California, Berkeley. He joined the School of Physics and Material Science at East China Normal University, as a Zijiang Youth Scholar Faculty Member. Since March 2016, he is serving as Institute of Condensed Matter Physics Director at School of Physics and Material Science, ECNU. Dr. Yang’s research is in the field of computational condensed matter physics and computational materials science and focuses on the application of atomistic methods for simulating thermodynamic and kinetic properties of metals and binary alloys, development calculation and characterization methods for the surfaces and interfaces of molten alloys. Dr. Yang has co-authored 23 peer-reviewed manuscripts, including 2 Phys. Rev. Lett. papers and 4 Acta Materialia papers. He has delivered over 15 invited lectures. Dr. Yang was awarded the Excellent Doctoral Dissertation Award of Shanghai City and was the 2018 recipient of the East China Normal University Natural Science Youth Award.