摘要
采用工业法制备了（Ｙ，Ｍｇ）ＰＳＺ／ＭｇＡｌ２Ｏ４陶瓷材料，在１１００℃热处理过程中，材料展示了良好的耐高温老化性。微观分析结果表明：材料在热处理过程中产生ｃＺｒＯ２→ｃ′ＺｒＯ２＋ｔＺｒＯ２＋ＭｇＯ形式的共析分解反应；同时，材料中存在ＭｇＯ稳定和Ｙ２Ｏ３稳定的三种形式的四方析出体，其中Ｙ２Ｏ３稳定的“花呢”（“ｔｗｅｅｄ”）和“群团”（“ｃｏｌｏｎｙ”
Finegrained (Y,Mg) PSZ/MgAl 2O 4 ceramics was prepared similar to the processing method of conventional Mg PSZ.This kind of material exhibits very good thermal stability at 1100℃.The mechanical properties of the material improve gradually at 1100℃ and the material possesses a strength of 671MPa and toughness of 15.27MPa·m 1/2 even the ageing time reached 800h.The development of microstructure and phase composition was confirmed with XRD and TEM/EDAX.The results show that there exists a new sub eutectoid decomposition reaction: cZrO 2c′ZrO 2+t ZrO 2+MgO which is different from the traditional decomposition of commercial Mg PSZ without Y 2O 3 addition.Furthermore,two kinds of precipitations can be indentified according to the differences of stabilizer and their existing forms.It is found that the “tweed”and“colony”during t ZrO 2 phase,which are rich in Y 2O 3,can grow up and lead to the increase of the transformable t ZrO 2 during the process of heat treatment.It is the transformable t ZrO 2 that plays an important role in toughening the matrix by using the sub eutectoid decomposition.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
1996年第5期498-503,共6页
Journal of The Chinese Ceramic Society
基金
显微镜中心资助项目
关键词
钇
镁
老化
结构
氧化物陶瓷
magnesium and yttria partially stabilized zirconia/spinel ceramics,high temperature degradation resistance,sub eutectoid decompositoin reaction,microstructure
