摘要
透明YAG多晶陶瓷具有容易制造、成本低、尺寸大、掺杂浓度高、热导率高、耐热冲击性好、可大批量生产、易实现多层和多功能的陶瓷结构等优点 ,使得它作为激光介质而成为单晶的强有力的替代者。本实验以Y2 O3、Al(NO3) 3·9H2 O、(NH4 ) 2 SO4 为原料 ,尿素为沉淀剂 ,正硅酸乙酯作为添加剂 ,采用均相共沉淀法制备出YAG前驱体粉末 ,在沉淀过程中采用静电稳定、聚合物空间位阻以及共沸方法相结合有效地防止了纳米颗粒硬团聚的形成 ,YAG前驱体颗粒尺寸小于 5 0nm ,并对反应过程中pH值的变化进行研究。采用DTA TG、IR、XRD和TEM测试手段对粉末材料进行了表征 ,根据Scherrer公式计算出晶粒大小 ,研究了晶粒尺寸分布及其变化情况。研究结果表明 :前驱体粉末经过12 0 0℃温度烧结后 ,全部转化YAG相 ,其晶粒尺寸小于 5 0nm ,随着烧结温度升高 ,晶粒平均尺寸增大。
Transparent polycrystalline Y 3Al 5O 12 (YAG) ceramics have the features of easy fabrication, less expense, large size sample, high thermal conductivity, high thermal stability, mass-production suitability, multi-layer and multi-function, which makes them a strong substitute for single crystal. The YAG precursor powders are prepared by homogeneous coprecipitation method using Y 2O 3, Al(NO 3) 3·9H 2O, (NH 4) 2SO 4, urea as precipitator, TEOS as additive. The hard agglomerates are prevented by the electrostatic and polymeric stabilization combined with azeotropic distillation. The precursor powder size is less than 50nm. The study is carried on the pH changes during the reaction. The precipitants are characterized by DTA/TG, IR, XRD and TEM., and the crystal size is calculated by the Scherrer formula. The distribution and change of crystal size are studied at the same time. It is found that all precursor powders completely transform to YAG phase calcined at 1 200℃, and all crystal size is smaller than 50nm, and the crystal mean size grows with the temperature increasing.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2004年第6期831-834,共4页
Journal of Materials Science and Engineering
基金
教育部优秀教师资助项目
