GRAIN-SIZE-DEPENDENT TRANSFORMATION BEHAVIOR IN POLYCRYSTALLINE TETRAGONAL ZIRCONIA
GRAIN-SIZE-DEPENDENT TRANSFORMATION BEHAVIOR IN POLYCRYSTALLINE TETRAGONAL ZIRCONIA
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DOI：
10.1111/j.1151-2916.1992.tb07832.x
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发表时间：
1992-03-01
影响因子：
3.9
通讯作者：
SWAIN, MV
中科院分区：
文献类型：
--
作者：
BECHER, PF;SWAIN, MV
本文介绍了多晶氧化锆中四方相转变行为的实验观察结果及其对增韧的贡献。 考虑相变热力学和残余应力的分析来描述晶粒尺寸对四方-单斜相变温度的影响。 该模型是基于促进局部内部拉伸应力集中的转变，其影响尺度与晶粒尺寸。 的马氏体开始温度晶粒尺寸的行为在多晶四氧化锆含有12摩尔%的氧化铈（12 CeTZP）的观察支持的分析。 接下来，分析考虑了相变增韧贡献Δ K（T）和相变区尺寸r（T）的晶粒尺寸依赖行为。 四方到单斜（t-to-m）形成温度M（s）随着四方晶粒尺寸d的增加而增加。 氧化锆-12摩尔%二氧化铈（12 CeTZP）和2 YTZP陶瓷的实验结果说明了预测形式的晶粒尺寸依赖性Δ K（T）和r（T）。 分析模型还描述了在2mol%氧化钇掺杂的多晶四氧化锆（2 YTZP）中观察到的相变增韧贡献Δ K（T）的温度依赖性。
Experimental observations of the tetragonal phase transformation behavior in polycrystalline zirconias and the related toughening contribution are presented. An analysis which considers transformation thermodynamics and residual stresses is developed to describe the influence of grain size on tetragonal-to-monoclinic transformation temperature. The model is based on the promotion of the transformation by local internal tensile stress concentrations whose effects scale with grain size. The analysis is supported by observations of the martensite start temperature-grain size behavior in polycrystalline tetragonal zirconia containing 12 mol% ceria (12CeTZP). Next, the analysis considers the grain-size-dependent behavior of the transformation-toughening contribution, DELTA-K(T), and the transformation zone size, r(T). The tetragonal-to-monoclinic (t-to-m) formation temperature, M(s), increases with increase in tetragonal grain size, d. Experimental results for zirconia-12 mol% ceria (12CeTZP) and 2YTZP ceramics illustrate the predicted forms of the grain size dependencies for DELTA-K(T) and r(T). The analytical model also describes the temperature dependence of the transformation-toughening contribution DELTA-K(T) observed in 2 mol% yttria-doped polycrystalline tetragonal zirconias (2YTZP).