Rapid Nondiffusional Penetration of Oxide Melts along Grain Boundaries of Oxide Ceramics

Abstract

Interaction of the liquid phase with the grain boundaries of solids and a rapid mass transport in solids were studied in the present work with a CuO ceramic melt of the Bi 2 O 3 system as an example. Anomalously rapid penetration of the liquid phase along the grain boundaries of a solid ceramic material was observed. The velocity and activation energy of the process were each determined. A mechanism for the development of a grain-boundary liquid channel in the kinetic mode, when the channel growth rate is reactionlimited, was proposed. This mechanism leads to the formation of a liquid-channel grain-boundary structure (LGBS) in solids. It was demonstrated that liquid can interact with one-dimensional as well as two-dimensional defects in solids.

Surface ionics: A brief review

“…[58][59][60][61][62] After the emergence of high resolution transmission electron microscopy, 63 thin intergranular amorphous films were dis- covered in numerous ceramic composites. The study of microstructures demonstrated that most of wetting phase is located at the triple grain junctions.…”

Mechanisms of Accelerated Oxidation of Copper in the Presence of Molten Oxides

“…According to references [16][17][18], the grain-boundary (GB) wetting can take place in oxide scale formed on the Cu surface during high temperature oxidation of the Bi 2 O 3 -coated Cu at 770 8C. Let us consider the GB wetting using the Bi 2 CuO 4 -Bi 2 O 3 system as an example.…”