AlN和AlN/BN层状复合陶瓷的高温氧化行为

Oxidation Behavior of AlN and AlN/BN Laminated Composites Ceramics at High Temperatures

摘要:

采用循环氧化法对单相AlN和层状AlN/h-BN复合陶瓷在1000及1300 ℃空气中的氧化动力学曲线进行研究。结果指出，在1000 ℃时，层状AlN/h-BN复合陶瓷的氧化增量低于单相AlN陶瓷；在1300 ℃时，其氧化动力学曲线分为缓慢增重、快速氧化增重和抛物线增重3个阶段，由XRD分析及扫描电镜观察发现，在1300 ℃氧化30 h后，试样已不存在BN相，并且由于界面层BN的氧化挥发而残留有微孔

Abstract:

The oxidation kinetics curves of both AlN and AlN/BN laminated composite ceramics at 1000 and 1300 ℃ were studied using a cycle-oxidation method. The result shows that the weight increase of AlN/h-BN laminated ceramic composites is lower than AlN ceramic at 1000 ℃, and the oxidation dynamics curve of AlN/BN laminated composite ceramics could be divided into three courses at 1300 ℃: a slowly weight increase, a rapid weight increase and a parabola shape weight increase. The XRD analysis and SEM observations show that there was no BN inside the AlN/BN laminated composite ceramics after 1300 ℃ oxidation and the micropores remain due to the vaporizing of B2O3 oxidized by BN