Grain boundary characters and structures in oxide ceramics

In order to arbitrarily control grain boundary characters in oxide ceramics, a series of alumina and zirconia bicrystals were fabricated by a hot joining technique to obtain symmetric tilt grain boundaries which included small angle, CSL and high angle grain boundaries. HREM and AEM were applied to characterize the grain boundary atomic structures and chemical composition. In addition, grain boundary energies were investigated by a thermal grooving technique. As the result, grain boundary structures and energies were found to strongly depend on the grain boundary characters. The relationship between grain boundary characters, structures and energies were discussed in detail in the present articles.