Fabrication of Dense ZrO_2-Based Nano/Nano Type Composites by New Powder Preparation Method and Controlled Sintering Process

摘要

Fully densitified nanoano type composites of ZrO_2/Al_2O_3 were fabricated by a pulse electric current sintering (PECS) method. The starting solid-solution powders with a size less than 10nm were successfully synthesized by a chemical process. Fast sintering with a high heating rates exhibited more enhanced denstification than slow sintering. Also, the grain size of the material by fast sintering was less than that by slow sintering. TEM observation showed that yttrium-stabilized ZrO_2/10mol%Al_2O_3 composite consisted of homogeneous and very fine ZtO_2 matrix grains less than 50nm, and that Al_2O_3 particles with a few nano-meters were homogeneously dispersed into the ZrO_2 matrix. The obtained mamocomposites showed significantly improved mechanical properties and plasticity at low temperature.