가수분해 조건에 따른 지르코니아 입자의 응집 특성

Abstract

Yttria stabilized zirconia was synthesized by urea hydrolysis and the agglomeration and dispersion behaviors among particles were investigated. Primary Yttria-stabilized zirconia particles were firstly obtained by heating of the mixing solution of zirconium oxychloride, yttrium nitride and urea. Hydrolysis temperature was controlled to 85~95 oC. Precipitates were washed by ultrasonic and filtered by a centrifugal separator. Drying method was performed by a microwave oven. Obtained precipitates were calcined at 850 oC for 1hour to produce crystalline powders and then attrition-milled for 12hours. All of synthesized zirconia powders were composed of tetragonal and nanosized particles regardless of hydrolysis temperature. Activated powder for sintering was obtained by the hydrolysis reaction of 90 oC, which was exhibited the less-agglomeration, small particle size and high surface area.