Optimizing colloidal processing of zirconia suspensions prepared with commercial powder

GUSTAVO SUÁREZ; TOHRU S SUZUKI; BYUNG-KOOG JANG; TETSUO UCHIKOSHI; YOSHIO SAKKA

Tsukuba, Japon.

Workshop; 2do NIMS-KIER workshop internacional; 2009

Zirconia materials were widely studied for many years and are still under research. Many of their properties like superplasticity, transparency, hardness or electrical conductivity are being improved. One of today’s most challenging goals in the ceramic science is the fabrication of large bodies suitable to be tested in industrial scale. For this reason it is very important to study the optimum colloidal processing of commercial powders. In this work we are optimizing the colloidal processing of zirconia with yttria and zirconia with carbon nanotubes (CNT) addition in aqueous suspensions. Bead-milling is similar to an attrition milling but working at 4000 rpm with a grinding media of zirconia balls with an average diameter size of 50, 30 or 15 microns. The suspension presents agglomeration that can be completely re-dispersed by bead-milling treatment. Zirconia with 5 % of CNT presents an agglomeration free and well mixed appearance after treatment. Slip casting lead to a high dense green compact. Sintering of bead-milling suspension leads to a reduction in the sintering temperature.