摘要
采用电熔融喷吹法制备不同氧化钙含量部分稳定氧化锆粉体(Ca-PSZ),发现以该粉体为原料的制品在烧结过程中易出现开裂现象,采用阿基米德法和X射线衍射仪分析经不同温度和时间热处理的样品的密度和相组成寻找造成开裂的原因。研究发现:用熔融喷吹法制备的氧化钙部分稳定氧化锆粉体中稳定相一部分为Ca2+稳定氧化锆,一部分为粒径尺寸小于相变临界尺寸的无稳定剂介稳氧化锆;1200℃下热处理电熔喷吹法制备的部分稳定氧化锆粉体可促进其微观形貌的完善和晶粒的长大,提高样品密度;当热处理温度为1500℃,晶粒尺寸超过相变临界尺寸(>14.34nm),样品中的介稳相氧化锆会分解生成单斜相氧化锆,导致样品稳定度和密度急剧降低。
Partially stabilized zirconium （PSZ） powder with various CaO content was prepared by adopting the electric melting and blowing process. Density and phase composition of samples after heat treatment were analyzed by employing Archimedes Method and X-ray diffraction. It was found that the PSZ powder prepared in such a way is consist of two phases： Ca2＋ stabilized ZrO2, and stablizer free ZrO2 with the particle size smaller than the critical size of phase transformation. Heat treatment of Ca-PSZ powders can promote the perfection of its microstructure and the growth of crystal particle, and consequently improve the density of the samples. The sample achieved a particle size of 14.34nm, the critical size of phase thansformation, after heated at 1200℃. When heated under 1500℃ however, the particle size of samples surpasses the critical size of phase transformation （〉14.34nm）, causing the decomposition of metastable T- ZrO2 into M-ZrO2, and in turn leading to sharp drops in stability and density of samples.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2012年第6期875-879,共5页
Journal of Materials Science and Engineering
关键词
钙稳定氧化锆
晶粒尺寸
电熔法
相变
Ca-PSZ
particle size
electric melting process
phase transformation
