不同Z值β-SiAlON的显微结构与力学性能  

Microstructure and mechanical properties of β-SiAlON with different Z values

作　　者：董鹏莉[1] 张梅[1] 郭敏[1] 王习东[2] 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]北京大学工学院,北京100871

出　　处：《耐火材料》2009年第1期23-26,30,共5页Refractories

基　　金：国家科技支撑计划(2006BAC21B02-1、2007BAB24B03);国家自然科学基金重点基金(50372004、50772004、50425415);国家973项目(2007CB613608)资助

摘　　要：在1773K、埋Si3N4粉气氛下，以Si、Al和Al2O3（均为分析纯）为原料合成了Z值分别为0．6、1．3、3．0和4．0的β—SiAlON。试验发现：随着所合成β—SiAlON的Z值从0．6增加至4．0，反应产物中逐渐有Al2O3剩余并生成15R（SiAl4O2N4），而且β—SiAlON的晶体形貌也有较大变化：Z=0．6～3．0时，β—SiAlON由细小晶须伴生转变为具有较大直径和长径比的六方柱状晶交织，且具有较完整的晶体结构，随着Z值的增加，材料的耐压强度和抗折强度同时提高；Z=4．0时，晶体形貌则是片状和具有较大长径比的长片状晶相互交错，和Z=3．0相比，材料的耐压和抗折强度有所下降．这主要取决于不同Z值β-SiAlON的不同晶体形貌及断裂方式。β-SiAlON with different Z values （0.6, 1. 3,3.0 and 4.0） has been synthesized by using analytically pure Si,Al and Al2O3 as starting materials fired at 1 773 K covered with Si3N4 powder. The experiment found that as Z value increased from 0.6 to 4.0, remained Al2O3 was found in reaction products and 15R （SiAl4O2 N4） formed,and the crystal morphology of β-SiAlON changed obviously： When Z = 0. 6 - 3.0, small whiskers β-SiAlON changed into interwoven hexagonal columnar crystals with long diameter and high slenderness ratio,and the crystat structure was complete. As Z value increased,the crushing strength and MOR of the material enhanced. When Z=4. 0,the flaky crystal and the straight crystal with high slenderness ratio interlaced with each other and the crushing strength and MOR decreased compared with those when Z=3.0. It is mainly depend on the different microstructure morphology and fracture mechanism of β-SiAlON with different Z values.

关 键 词：Β-SIALON 显微结构 晶须 耐压强度 抗折强度 

分 类 号：TQ175.712[化学工程—硅酸盐工业] TQ174.758