Isothermal Propagation of Martensite in Y2O3- Partially Stabilized Zirconia Ceramics
Isothermal Propagation of Martensite in Y2O3- Partially Stabilized Zirconia Ceramics
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Y2O3-部分稳定氧化锆陶瓷中马氏体的等温扩展
DOI：
10.2497/jjspm.33.356
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
H. Okinaka
中科院分区：
文献类型：
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作者：
N. Nakanishi;T. Shigematsu;T. Sugimura;H. Okinaka
实验发现，2.2和5.0 mol%-PSZ陶瓷在1873 K的空气中烧结后，在423 ~ 628 K的温度范围内，马氏体相变进行等温时效。实验结果表明，Y2O3-PSZ陶瓷在473 K左右发生的所谓降解主要是由于等温生成的马氏体膨胀引起的微裂纹扩展。为了弄清马氏体在试样表面先形成再向内部扩散的等温扩展机制，作者提出了一个可以解释实验中得到的时间-温度转变图c型行为的模型。由于以下三个因素(1)烧结温度，(2)环境和(3)氧离子的扩散性被认为对c曲线有重要影响，因此这些问题必须在以后进行实验研究。
The authors have experimentally found that the martensitic transformation propagates isothermally during aging the 2.2 and 5.0 mol%-PSZ ceramics in the temperature range about 423-628 K after being sintered at 1873 K in air. As a result of this experiment, it was suggested that the so-called degradation of Y2O3-PSZ ceramics occurring at temperature around 473 K is mainly due to the microcrack propagation induced by the expansion of isothermally produced martensite. To make clear the mechanism of the isothermal propagation of martensite, which is first formed at the specimen surface region and then propagates into the interior, the authors proposed a model which can explain the C-type behaviour of time-temperaturetransformation diagram obtained in this experiment. Since the following three factors, (i) sintering temperature, (ii) circumstance and (iii) the diffusibility of oxygen ions, are thought to have an important effect upon the C-curves, these problems must be experimentally studied hereafter.