The Post-treatments of Aluminum Oxynitride(AlON) Powders Synthesized by the Carbothermal Reduction and Nitriding Process

Yingying Chen,1

Qinggang Li,2,*Email

Zhi Wang,1,**Email

Guopu Shi,1

Junyan Wu1 

Mengyong Sun3

1School of Material Science and Engineering, University of Jinan, Jinan 250022, China

2Shandong Provincial Key Laboratory of Preparation and Measurement of Building Materials, Jinan 250022, China

3Shandong Province Key Research and Development Plan, Yantai, 264003, China

Abstract

The post-treatments including ultrasonic dispersion, freeze-drying and ball milling were used to reduce the particle size of Aluminum oxynitride (AlON) powders, which were synthesized by the carbothermal reduction and nitriding process. Effects of post-treatment methods and time on the microstructure and particle size distribution were systematically evaluated. Results show that ball milling for 12 h can effectively break up some large particles caused by agglomeration and reduce the particle size from 19.61 μm to 1.347 μm. The preparation of AlON transparent ceramics was explored preliminarily. The AlON powders with 0.4 wt% Y2O3 and 0.02 wt% La2O3 were used to prepare the green body by dry pressing and cold isostatic pressing. Then the ceramic green body was pressless sintered with flowing nitrogen atmosphere at 1875℃ for 24 h, 6 h and 3 h respectively. When the sintering schedule was 3 h heat preservation, the density of AlON ceramic has been greatly improved.

The Post-treatments of Aluminum Oxynitride(AlON) Powders Synthesized by the Carbothermal Reduction and Nitriding Process