摘要
以铝粉、B2 O3 粉和TiO2 粉为原料 ,研究了埋炭还原气氛下B2 O3 加入量、温度和气氛 3种工艺因素对铝热还原法制备Al2 O3 -TiB2 复相陶瓷的影响。结果表明 :(1)在还原气氛下用铝热还原法可以制备Al2 O3 -TiB2 复相陶瓷。 (2 )原料中B2 O3 过量 ,则有 9Al2 O3 ·2B2 O3 相生成。 (3)烧成温度在 90 0℃时铝热反应基本未开始 ;10 0 0℃时有大量TiB2 和α Al2 O3 相生成 ,α Al2 O3 呈长方柱状 ,晶粒较大 ,TiB2分布在α Al2 O3 颗粒之间 ,晶粒细小 ;10 0 0℃以上时 ,反应产物的相组成变化不大 ,但 15 0 0℃后 ,TiB2晶粒较大 ,尺寸为 0 .5～ 3μm。
Effects of three technological factors of B 2O 3 addition,temperature and atmosphere on the preparation of Al 2O 3-TiB 2 composite by aluminothermic reaction method in reduction atmosphere were investigated using Al powder,B 2O 3 powder and TiO 2 powder as starting materials by thermal dynamic calculation,XRD analysis,SEM and EPMA.The results show that:(1) Al 2O 3-TiB 2 composite can be prepared by aluminothermic reaction in reduction atmosphere.(2)When B 2O 3 content in starting materials is over-excessive,the 9Al 2O 3·2B 2O 3 phase would be formed.(3)At 900 ℃,aluminothermic reaction didn't start and at 1000 ℃ or above,a lot of TiB 2and α-Al 2O 3 can be obtained;α-Al 2O 3 crystalline is of rectangle shape and large and TiB 2 granular is small and gathers among α-Al 2O 3crystalline.At above 1000 ℃,the phase composition of the reaction product don't change a lot and after firing at 1500 ℃ for 3 hours,the size of TiB 2 is 0.5～3 μm.
出处
《耐火材料》
CAS
北大核心
2002年第4期211-212,共2页
Refractories
基金
湖北省教育厅 2 0 0 1年度科学研究计划资助项目( 2 0 0 1D190 0 1)
