Ordered Liquid Aluminum at the Interface with Sapphire

• Published in: Science (American Association for the Advancement of Science) 2005-10, Vol.310 (5748), p.661-663
• Main Authors: Oh, S. H, Kauffmann, Y, Scheu, C, Kaplan, W. D, Růhle, M
• Format: Article
• Language: English
• Subjects: Aluminum; Analysis; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Crystals; Density; Electron microscopes; Evidence; Exact sciences and technology; Growth from melts; zone melting and refining; Heat; Laboratory Equipment; Liquids; Materials science; Methods of crystal growth; physics of crystal growth; Phase transitions; Physics; Solid-fluid interfaces; Solidification; Specific gravity; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Testing; Video Equipment; Videotape Recorders
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1118611

Understanding the nature of solid-liquid interfaces is important for many processes of technological interest, such as solidification, liquid-phase epitaxial growth, wetting, liquid-phase joining, crystal growth, and lubrication. Recent studies have reported on indirect evidence of density fluctuations at solid-liquid interfaces on the basis of x-ray scattering methods that have been complemented by atomistic simulations. We provide evidence for ordering of liquid atoms adjacent to an interface with a crystal, based on real-time high-temperature observations of alumina-aluminum solid-liquid interfaces at the atomic-length scale. In addition, crystal growth of alumina into liquid aluminum, facilitated by interfacial transport of oxygen from the microscope column, was observed in situ with the use of high-resolution transmission electron microscopy.