溶胶包覆对BaTiO_3陶瓷晶粒尺寸的影响

Effect of Sol-gel Coated Method on Grain Size of BaTiO_3 Ceramic

采用溶胶-凝胶技术制备BaTiO3溶胶,然后把该溶胶与晶粒尺寸为100 nm的水热法BaTiO3粉体混合在一起,形成了同组成溶胶对同组成粉体的包覆.结果表明:溶胶的掺入降低了试样的烧结温度,包覆能抑制晶粒长大,试样致密成分均一.最终试样晶粒尺寸由包覆前的2～5μm,减小到包覆后的0.4～1μm,而且试样较致密,其密度基本在理论密度的95%以上.

BaTiO3 sol was prepared by sol-gel technology. The sol was mixed with ultra-fine BaTiO3which grain size was 100 nm and coated on the surface of the BaTiO3 powder prepared with hydrothermal method. The sintering temperature of specimens will decrease and the growth of grain is prevented with this method. It is found that the grain sizes of the coated specimens are from 400 nm to 1 μm and its density is above 95% of theory density mostly, while the grain sizes of the specimens without coated sol are from 2 μm to 5 μm.