Fabrication of nano Y-TZP materials by superhigh pressure compaction

Y-TZP nanoceramics have been fabricated by superhigh pressure compacting and pressureless sintering. It was found that, by applying superhigh pressure of about 3GPa, the green compacts with a relative density of about 60% could be obtained, which was 12% higher than that by a normal cold isostatic pressure of 450 MPa. The obvious advantage of the higher relative density of the green compact is that the sintering temperature could be decreased to as low as 1050 degreesC. The reason for the good sintering behavior is believed to be both the increase in contact points between the particles and the decrease in pore size. Nano Y-TZP ceramics with grain size of about 80 nm could be obtained when sintered at 1050 degreesC for 5 h. (C) 2001 Elsevier Science Ltd. All rights reserved.