添加La_(2)O_(3)快速无压烧结制备高红外透过率AlON陶瓷  

Highly Infrared Transparent AlON Ceramics Doped with La_(2)O_(3) via Fast Pressureless Sintering

作　　者：郗雪敏 马莉娅 郭浩然[1] 单英春[1] 韩晓光[1] 徐久军[1] 李江涛[2] XI Xuemin;MA Liya;GUO Haoran;SHAN Yingchun;HAN Xiaoguang;XU Jiujun;Li Jiangtao(Department of Materials Science and Engineering,Dalian Maritime University,Dalian 116026,Liaoning,China;Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100080,China)

机构地区：[1]大连海事大学材料系,辽宁大连116026 [2]中国科学院理化技术研究所,北京100080

出　　处：《硅酸盐学报》2024年第3期794-803,共10页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(52372058);中央高校基本科研业务费专项资金资助(3132023515);大连市科技创新基金重点学科重大课题项目(2021JJ11CG002)资助。

摘　　要：利用La_(2)O_(3)作为烧结助剂,分别采用D50为1.1μm和2.0μm的AlON粉体,在1880℃保温2.5 h快速无压烧结成功制备了红外透过率达80%~84%(3850 nm处)的AlON陶瓷。基于AlON粉体粒度研究了La_(2)O_(3)掺量对陶瓷透过率的影响规律,并通过研究高透光性AlON陶瓷烧结过程升温阶段的物相组成、微观结构及致密化进程,揭示了其致密化机制。结果表明,La_(2)O_(3)对AlON分解具有一定的抑制作用,使样品中的α-Al_(2)O_(3)含量较低,从而避免了颗粒的早期团聚、粗化等,为后期致密化烧结奠定了良好的基础,同时,高致密度高透光性AlON陶瓷的快速无压烧结制备表明La_(2)O_(3)能为后期烧结提供充足的动力。Introduction Transparent aluminum oxynitride(AlON)ceramics have superior optical transparency properties,high strength and hardness,having great potential applications as window,dome,and other optical components requiring high strength combined with optical transparency.Recent efforts are made to fabricate transparent AlON ceramics,i.e.,synthesis of high purity AlON powder,optimization of the particle size distribution of AlON powder,and doping with various additives in different amounts.In these works,sintering additives,such as Y_(2)O_(3),Y_(2)O_(3)/La_(2)O_(3),Y_(2)O_(3)/La_(2)O_(3)/MgO,etc.,are commonly used to accelerate densification process of Al ON.However,a long dwelling duration of≥6 h is generally required to eliminate pores to obtain a high transmittance in pressureless sintering.Although the dwelling duration of pressureless sintering AlON ceramics can be shortened to 2.5 h,it is crucial to carefully match the doping amount of Y_(2)O_(3) with the particle size of AlON powder.The excessive Y_(2)O_(3) doping can result in a significant decomposition of AlON intoα-Al_(2)O_(3) and Al N,and the massive formation ofα-Al_(2)O_(3) can lead to particle aggregation/coarsening,and even separation between components during the early stage of sintering,which in turn retards the subsequent densification process.Studies on using CaCO_(3) as an additive to fabricate AlON ceramics indicate that it should be a promising way to fabricate highly transparent AlON ceramics via suppressing AlON decomposition during heating with sintering additive.In this paper,La_(2)O_(3) was respectively doped to AlON powders with median particle size(D_(50))of 1.1μm and 2.0μm to prepared transparent AlON ceramics via pressureless sintering(PS)at 1880℃for 2.5 h.The effect of La_(2)O_(3) doping amount on the transmittance of AlON ceramics was investigated,and the phase composition,microstructure and densification process of samples during heating were monitored to investigate the fast densification mechanism of AlON.Methods Pure Al

关 键 词：氮氧化铝 氧化镧 烧结助剂 粉体粒度 透明陶瓷 无压烧结 

分 类 号：TQ174[化学工程—陶瓷工业]