1988 年 9 巻 6 号 p. 434-439
The gel structure in the ZrO2-SiO2 system, produced by the sol-gel process and the ultrasonic spray pyrolysis method using a solution of ZrOCl2·8 H2O-Si(OC2H5)4-C2H5OH-H2O system (mother solution), was investigated in relation to the phase crystallized by heating, from the standing point of the surface and the interface of ZrO2 and SiO2. The siloxane polymer of compound system changed from linear to three dimensional type with an increase in the molar ratio 'r' of added H2O. In this case, the crystallization temperature of SiO2 increased and the transformation rate of T-to M-ZrO2 decreased, due to the mutual 'block effect' of SiO2 and ZrO2. Without the block effect, T-ZrO2 was converted utterly to M-ZrO2. The strain energy caused by the crystallization of SiO2 at the interface preserved the metastable T-ZrO2. The morphology such as the dispersive state of two oxide components should be considered for the study on the transformation of ZrO2. The spherical ZrO2-SiO2 system particles were successfully produced by the ultrasonic spray pyrolysis method from the mother solution which had been preliminarily hydrolyzed.