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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．
In this paper, the effects of dispersant on the colloidal properties and rheological properties of silicon nitride powders were investigated. The results showed that the isoelectric point of Si3N4 powders was at pH = 4.2 and the maximum Zeta potential of powders was around pH = 11 . The introduction of dispersant will make its isoelectric point displacement, the displacement and the amount of dispersant, the best amount of dispersant between 0.8 ~ 1.2wt%. The silicon nitride slurry is a non-Newtonian time-dependent fluid. When the amount of dispersant is low, the thixotropic properties of the slurry are thixotropic. With the increase of the amount of dispersant, the thixotropy gradually disappears. When the amount of dispersant reaches 1.2wt%, the slurry becomes approximate Bingham fluid. With the amount of dispersant Increase, the slurry showed a weak positive thixotropy.