陶瓷微球新型直接滴定成型工艺研究

以平均粒径为0.1~0.5μm的SnO₂粉为原料，通过凝胶注模成型制备SnO₂浆料，并使用滴定针筒将浆料直接滴定于旋转的金属基超疏水表面，使SnO₂液滴在不同条件下的旋转金属基超疏水表面固化成球。研究了液滴尺寸、成型时间、固含量等因素对微球成型的影响规律，结果表明:直接滴定成型的SnO₂陶瓷微球的球形度十分理想，球形度大于常规滴定成型法，并且可成型出直径0.1~0.5 mm的陶瓷微球；微球的球形度随固含量的增加而增大，随液滴尺寸的增加而减小，随固化时间的增加而减小；当液滴尺寸调整为0.05 mm时，使用凝胶注模工艺优化后的固含量为80%的SnO₂粉浆，在60℃时干燥固化30 min，该条件下获得的SnO₂陶瓷微球具有最高球形度，可达到99.5%；微球球坯烧结前后的表面微观组织结构较为均匀，烧结后可保持完整的球体形状。 

Study on New Direct Titration Process of Ceramic Microspheres

The gelcasting SnO₂ slurry was prepared with SnO₂ powders with the average size of 0.1-0.5 μm as raw material. The slurry was directly titrated on the rotating metal based super hydrophobic surface by titration syringe, so that SnO₂ droplets could be solidified into balls on the super hydrophobic rotating metal base surface under different conditions. The effects of droplet size, forming time and solid content on microsphere molding were studied. The results showed that the sphericity of SnO₂ ceramic microsphere formed by direct titration was ideal, which was higher than that by conventional titration method, and the diameter of ceramic microspheres was 0.1-0.5 mm. The sphericity of the microspheres increased with the increase of solid content, and decreased with the increase of droplet size and the increase of curing time. When the droplet size was adjusted to 0.05 mm and the optimized SnO₂ powder with a solid was by gel casting process in 30 min at 60℃, the SnO₂ ceramic microspheres with the highest sphericity up to 99.5% could be obtained. The surface microstructure of the microsphere was uniform and the sphere shape could be maitained after sintering.