摘要
研究了制备β″-Al_2O_3陶瓷粉料的喷雾干燥工艺,选择了Al_2O_3-LiOH·NaOH水溶液泥浆的喷雾干燥工艺。仅0.25wt％的木质素磺酸盐或0.5wt％的阿拉伯胶,即可使Al_2O_3含量达45wt％左右的泥浆的相对粘度降至2以下。这种喷雾干燥粉料的松装密度d_1为0.8—0.9g/cm^3,振实密度d_t在1.0g/cm^3上下,流动度达25—27cm^3/s·cm^2。直接用这种粉料压坯,可制出烧结密度高于3.21g/cm^3,300℃电阻率6—7Ω·cm的β″-Al_2O_3陶瓷管。其它碱源的粉料则须经煅烧后再压坯方能烧结到较高的密度。
Spray drying as a method for preparing β″-Al_2O_3 powders has been investigated. A kind of spray drying technique using for Al_2O_3-LiOH.NaOH solution slurry was selected after compared the properties of several spray-dried powders prepared by different approches. The relative viscosity of this water based alkaline slurry containing about 45wt% Al_2O_3 can be lowered to a value less than 2 by adding 0.25wt％ lignosulfonates or 0.5 wt％ gum arabic. Spray-dried powder with loose density of 0.8—0.9g/cm^3. tap density of 1.0g/cm^2 and fluidity of 25—27cm^3/s.cm^2 has been prepared from the above slurry. Without calcination, this kind of powder can be isostatically pressed and then sintered to a density of 3.21g/cm^2. The Na ion resistivity of the sintered sample is 6—7Ω·cm st 300℃. Spray-dried powders using other salts as alkali sources have to be calcinated before pressing to obtain a higher fired density
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
1989年第3期278-283,共6页
Journal of The Chinese Ceramic Society
