Transformation Toughening in Zirconia-Based Ceramics

这项建议是为了继续研究含ZrO_2陶瓷的相变增韧。具体地说，研究将集中在：i)使致密相变增韧具有细晶尺寸的Mg-PSZ，而不是当前一代的韧性mg-PSZ是粒状的、多孔的并且包含不需要的第二相，ii)研究三元Mg，Y-PSZ的结构-性能关系，特别是探索颗粒形态和因此的共格应力的影响，在裂纹尖端应力诱导相变方面，研究了“超韧”Mg-PSZ的应力诱导亚临界相变的机理，以及Y-PSZ单晶显微硬度压痕周围的相变，特别是位错成核的自催化相变。

This proposal is for the continuation of research on transformation toughening in ZrO2-containig ceramics. Specifically, the research will focus on i) making dense transformation toughened Mg-PSZ with fine grain size, in contrast to the current generation of tough Mg- PSZ's which are course grained, porous, and contain unwanted second phases, ii)studying structure-property relationships in ternary Mg, Y-PSZ's, particularly probing the effect of particle morphology and hence coherency stresses, on the crack tip stress-induced transformation, iii) Studying the mechanics of stress-induced subcritical transformation which in "supertough" Mg-PSZ can occur before any visible surface microcracks, and iv) studying transformation around microhardness indents in Y-PSZ single crystals, particularly the dislocation-nucleated autocatalytic transformation.