La^(3+)对MgAl_(2)O_(4)透明陶瓷致密化过程、光学及力学性能的影响  

Effect of La^(3+)on Densification Process,Optical and Mechanical Properties of MgAl_(2)O_(4) Transparent Ceramics

作　　者：邢钰培 刘鹏 韩丹 章健[2] 王俊 马杰 徐晓东 XING Yupei;LIU Peng;HAN Dan;ZHANG Jian;WANG Jun;MA Jie;XU Xiaodong(Jiangsu Key Laboratory of Advanced Laser Materials and Devices,School of Physics and Electronic Engineering,Jiangsu Normal University,Xuzhou 221116,China;Research Center of Transparent Ceramics,Shanghai Institute of Ceramics,Chinese Academy of Science,Shanghai 201899,China)

机构地区：[1]江苏师范大学物理与电子工程学院,江苏省先进激光材料与器件重点实验室,徐州221116 [2]中国科学院上海硅酸盐研究所,透明陶瓷研究中心,上海201899

出　　处：《硅酸盐通报》2024年第3期1048-1057,共10页Bulletin of the Chinese Ceramic Society

基　　金：国家重点研发计划(2022YFB3705900)。

摘　　要：镁铝尖晶石(MgAl_(2)O_(4))透明陶瓷具有优异的光学和力学性能,在防弹装甲窗口、高马赫整流罩等方面得到了大量的应用。为实现MgAl_(2)O_(4)透明陶瓷的致密化,一般需要相对较高的烧结温度,然而高的烧结温度会导致陶瓷晶粒生长过大,影响其性能。因此通过引入合适的烧结助剂降低烧结温度,对于提升陶瓷性能和降低成本均具有很大的意义。本文以高纯商业MgAl_(2)O_(4)粉体为原料,La(OH)_(3)为烧结助剂,采用真空烧结结合热等静压后处理的方式,成功制备MgAl_(2)O_(4)透明陶瓷,并采用XRD、SEM等对透明陶瓷的微结构和相组成的演变以及性能进行表征。结果表明,La^(3+)在烧结早中期可有效提高陶瓷致密化速率,在烧结后期可抑制陶瓷晶粒生长。掺入0.01%(质量分数)La_(2)O_(3)后,MgAl_(2)O_(4)光学和力学综合性能优异,所需的热等静压烧结温度由1650℃降低到1600℃,相应平均晶粒尺寸由7μm减小到3μm。Magnesium aluminum spinel(MgAl_(2)O_(4))transparent ceramics have excellent optical and mechanical properties,which have been widely used in bulletproof armor windows and high Mach fairing.To achieve densification of MgAl_(2)O_(4)transparent ceramics,a relatively high sintering temperature is generally required.However,higher sintering temperature can lead to excessive grain growth of ceramics,which will affect its performance.Therefore,it is very significance for improving the performance and reducing costs of ceramics by introducing appropriate sintering aids to reduce its heat treatment temperature.In this article,the high-purity commercial MgAl_(2)O_(4)powders were used as raw materials and La(OH)_(3)powders were used as sintering aids.The MgAl_(2)O_(4)transparent ceramics were fabricated using vacuum sintering combined with hot isostatic pressing(HIP)post-treatment.The evolution of microstructure and phase composition were tested by XRD and SEM.The optical and mechanical properties of transparent ceramics were characterized using UV-Vis-NIR spectrophotometer and multifunctional mechanical material testing machine,respectively.The results indicate that La^(3+)effectively improves the densification rate of ceramics in the early and middle stages of sintering,and inhibits grain growth of ceramics in the later stages of sintering.After adding 0.01%(mass fraction)La_(2)O_(3),the optical and mechanical properties of MgAl_(2)O_(4)are excellent.The HIP sintering temperature required to achieve optimal optical quality is decreased from 1650℃to 1600℃and the corresponding average grain size is reduced from 7μm to 3μm.

关 键 词：MgAl_(2)O_(4) La^(3+) 透明陶瓷 烧结助剂 微结构 致密化 

分 类 号：TQ174[化学工程—陶瓷工业]