本文研究了分散剂对氮化硅粉体的胶体特性、流变特性的影响，结果发现：Si3N4（Starck）粉料的等电点在pH=4.2，粉料的最大Zeta电位在pH=11附近．分散剂的引入将使其等电点位移，其位移量与分散剂的用量有关，最佳分散剂用量在0.8～1．2wt％之间．该氮化硅浆料属非牛顿的依时性流体．当分散剂用量低时，浆料呈现反触变性，随分散剂用量的增加，触变性逐渐消失；当分散剂用量达1．2wt％时，浆料成为近似的宾汉流体；随着分散剂用量的进一步增加，浆料又呈现微弱的正触变性．
The effect of a dispersant on the electrokinetics and rheology of silicon nitride aqueous suspension with solids loading of
50wt% was investigated. The results indicated that the isoelectric point (IEP) of the silicon nitride powders is at the pH value of 4.2, and the
value of zeta potential is up to its maximum near pH value of 11. The IEP of the silicon nitride powders decreases with the addition of the dispersant and
the shift dependents on the amount of the dispersant. The suspension is a non-Newtonian time-dependent fluid. The optimum amount of the
dispersant is at the ranges from 0.8 to 1.2wt%, in which the suspension is near Bingham fluid. Beyond that range, the suspension
exhibits thixotropic behavior, or the suspension is an anti-thixotropy.
参考文献
| [1] | Lange F F. J. Am. Ceram. Soc., 1989, 72 (1): 3--15 2 Cameron C P, Raj R. J. Am. Ceram. Soc., 1990, 73 (7): 2032--2037 3 Bergstrom L, Bostedt E. Colloids Surf., 1990, 49: 183--197 4 Hunter R J. Zeta Potential in Colloid Science---Principles and Applications. New York: Academic Press, 1981 5 Hidber P C, Graule T J, Gauckler L J. J. Am. Ceram. Soc., 1996, 79 (7): 1857--1867 6 Hackley V A. J. Am. Ceram. Soc., 1997, 80 (9): 2315--2325 7 Greenwood R, Roncari E, Galassi C. J. Eu. Ceram. Soc., 1997, 17: 1393--1401 |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%