SiC浆料的流变性能研究

为制备结构均匀的多孔SiC陶瓷的料浆,本文比较了不同质量分数(40%~60%)的SiC浆料的剪切应力和黏度随剪切速率的变化.结果表明:浆料的等电点在3.6左右,Zeta电位值随着pH值的增加而减小,碱性环境下分散效果更好;用Casson方程拟合浆料的剪切应力,相关系数在0.98以上,随着固相含量的增加,拟合的极限粘度和屈服应力增加;当剪切速率达到100 s-1时,固相含量为40%~55%浆料的粘度都在1 Pa·s以下,固相含量为60% 的浆料粘度大概是2.1 Pa·s.

Rheological Property of SiC Slurry

In order to prepare the SiC slurry for porous ceramics, the variation of the shear stresses and viscosities of SiC slurries with different mass fraction (40%-60%) were investigated.The results show that the isoelectric point of the slurry is about 3.6, and zeta potential value decreases with the increase of pH value, the dispersing effect of the slurry in the alkaline condition is better.The correlation coefficients are both above 0.98 by fitting the shear stresses of SiC slurries based on Casson equation.The limit viscosities and yield stresses increase with the increase of the mass fraction.When the shear rate reaches 100 s-1, viscosities of slurries with the mass fraction ranging from 40% to 55% are below 1 Pa·s.The viscosity of the slurry with the mass fraction of 60% is 2.1 Pa·s.