摘要
通过热压烧结在1700℃,分别于Ar和N2气氛下制备了一系列SiC-Si3N4-Gd2O3陶瓷样品,采用X射线衍射技术分析了样品的相组成,确定了相关系。结果表明:在SiC-Si3N4-Gd2O3的二元子系统和三元系统中,除了二元化合物Si3N4.Gd2O3(M相)存在,尚有含氮稀土硅酸盐化合物Si2N2O 2Gd2O3(J相)和Gd10(SiO4)6N2(H相)生成。而这些化合物的生成主要是由于SiC、Si3N4粉料表面的杂质氧(以SiO2形式存在)参与了反应,由此引入的SiO2这一组分,使原三元系统扩大成为SiC-Si3N4-SiO2-Gd2O3四元系统。通过对产物相组成的分析,确定了在此四元系统中存在8个相容性四面体。基于上述结果,提出了1 700℃的SiC-Si3N4-Gd2O3准三元亚固相图、Si3N4-Gd2O3-SiO2三元亚固相图以及SiC-Si3N4-SiO2-Gd2O3四元亚固相图。
The samples of SiC-Si3N4-Gd203 system were prepared by a hot pressure sintering （HP） method in N2 and Ar atmospheres at 1 700 ℃. The phase compositions of the samples were analyzed by X-ray diffraction to determine the phase relations. The results show that, except for Si3N4-Gd203 （M phase）, two oxygen-rich rare-earth siliconoxynitrides Si2N20＂2Gd203 （J phase） and Gdlo（SiO4）6N2 （H phase）, are also formed in the ternary system and binary subsystems SiC-Si3Na-3d203 due to the presence of excess oxygen impurity in the starting powders of SiC and Si3N4. The ternary system was transformed into a quaternary system due to the introduction of SiO2. In the system, eight compatible tetrahedrons were determined. The subsolidus phase diagrams at 1 700 ℃ for the trinary SiC-Si3N4-GdzO3 system, Si3N4-d203-SiO2 system and the quaternary SiC-Si3N4-SiO2-Gd203 system could be proposed based on the results obtained.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2011年第10期1536-1540,共5页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(NSFC50962001)资助项目
关键词
碳化硅
氮化硅
氧化钆
相平衡:相图
silicon carbide
silicon nitride
gadolinium oxide
phase equilibrium
phase diagram
