Si_3N_4粉末表面的非均质成核法包覆及其浆料流变性的研究

SURFACE COATING WITH HETEROGENEOUS NUCLEATION OF Si_3N_4POWDER AND ITS RHEOLOGICAL PROPERTY

在研究Ｓｉ３Ｎ４ 粉末表面包覆工艺及各因素影响规律的基础上，确定了非均质成核法对Ｓｉ３Ｎ４ 粉末表面包覆改性的最佳工艺范围． 利用透射电镜、Ｘ射线粒度分布仪、粘度测定仪、ｚｅｔａ 电位测定仪对包覆前后Ｓｉ３Ｎ４ 浆料进行了分析． 结果表明：在最佳包覆工艺范围内，Ｓｉ３Ｎ４ 粉末表面均匀包覆一层Ａｌ（ＯＨ）３ ，并包覆后Ｓｉ３Ｎ４ 浆料的ｚｅｔａ 电位发生明显变化，粒度分布更加均匀，流变性能得到明显改善．

Each factor affecting Si 3N 4 surface coating for performance modification was investigated. On the basis of the effecting law of each factor, the optimum condition of Si 3N 4 surface coated by the heterogeneous nucleation was determined. Slurry of Si 3N 4 with and without coating was analyzed by TEM, X -ray powder, size distribution apparatus, viscometer, zeta potential apparatus. It is shown that, in the optimum condition range, the surface of Si 3N 4 coated uniformly by Al(OH) 3 and zeta potential in the coated Si 3N 4 slurry change obviously and size distribution is more uniformly, rheological property is much improved.