How do the grains slide in fine-grained zirconia polycrystals at high temperature?

Abstract

Degradation of mechanical properties of zirconia polycrystals is hardly discussed in terms of solution-precipitation grain-boundary sliding due to experimental controversies over imaging of intergranular amorphous phases at high and room temperatures. Here, the authors applied the techniques of mechanical spectroscopy and transmission electron microscopy (TEM) to shed light on the amorphization of grain interfaces at high temperature where the interface-reaction determines the behaviour of fine-grained zirconia polycrystals. They present mechanical spectroscopy results, which yield evidences of an intergranular amorphous phase in silica doped and high-purity zirconia at high temperature. Quenching of zirconia polycrystals reveals an intergranular amorphous phase on TEM images at room temperature.

High Temperature Internal Friction in Fine Grain and Nano-Crystalline Zirconia

“…Yttria-tetragonal ZrO 2 polycrystals (YTZP) is one of the most promising materials for mechanical applications due to its excellent strength and fracture toughness. Many studies on the high temperature plastic deformation of this material have been performed with different yttria contents [1][2][3][4][5]. In particular, fine-grained tetragonal zirconia exhibits superplastic flow as was shown by Wakai et al [6].…”