Microstructural Design of Grain Boundaries in Alumina Based Ceramics

摘要

Microstructural changes and grain boundary formation during liquid phase sintering were examined by experimental methods and then studied with computer simulations. Scanning and transmission electron microscopic observations of the alumina-anorthite (Al_2O_3-CaO-2SiO_2) system revealed the general features of liquid phase sintering such as wetting and rearrangement and also variation in the grain boundary structures. Monte Carlo (MC) and molecular dynamics (MD) methods were used to model the phenomena during liquid phase sintering and grain boundary formation. The MC simulation was able to represent the behaviors of wetting and rearrangement during liquid phase sintering. The MD method was found to be capable of simulating grain boundary formation and structures in ionic bonded ceramics.