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The morphological properties of powders with the same chemical composition in the system Al 2 O 3 -ZrO 2 -CeO 2 with the components precipitated in different sequences are investigated. The schemes used to obtain the precursors of this system make it possible to prepare powders with a prescribed chemical composition and high precipitation completeness and with individual particle sizes near 20 nm. The morphology, degree of agglomeration, and porous structure of the synthesized powders depend on the conditions under which the precursors are obtained.For ceramic materials the dispersity and granulometric composition of the initial powders are not simply size characteristics of the system, but rather they have a defining significance as technological parameters. The question of the need to take account of these parameters in order to obtain slips, intermediate products, and subsequently materials with the required structure was examined in P. O. Gribovskii's works [1]. Since nanopowders are being increasingly used in ceramics technology, questions concerning their producibility are very important [2 -4].The possibility of certifying powders using new-generation instrument technology for analyzing the particle-size range and granulometric composition makes it possible to advance validated assumptions and explain the behavior of powders within technological limits. For example, Ukrainian scientists have shown in a publication devoted to powders obtained by a chemical method in the system ZrO 2 -Y 2 O 3 that the fractal structure of xerogels depends on the sequence in which the components in this system are precipitated [5]; this dependence is reflected in the dimensional characteristics of the powders and affects the technological parameters, specifically, the filtration coefficient.Our experimental studies of the system Al 2 O 3 -ZrO 2 -CeO 2 as a basis for high-strength ceramics have shown that the precipitation sequence of the components affects the thermal-phase formation of precursors with the same chemical composition and grain composition of the microstructure of the ceramic [6,7].The objective of the present work is to examine in detail the morphological properties of powders with the same chemical composition which are obtained in the system Al 2 O 3 -ZrO 2 -CeO 2 with the components precipitated in different sequences.The following composition was chosen for the present investigations (molar content, %): 50 Al 2 O 3 -50 (88 ZrO 2 + 12 CeO 2 ). Powder precursors were obtained by the sol -gel method, which gives the best results for synthesis of complex oxide ceramic, giving compositions that are homogeneous and pure. Solutions of the following salts were obtained (1M): Ce(NO 3 ) 3 × 6H 2 O, ZrOCl 2 × 8H 2 O and Al(NO 3 ) 3 × 9H 2 O. Freshly prepared solutions were used in order to decrease the effect of the hydrolysis of the initial salts. A concentrated water solution of ammonia was used as a precipitator; the surfactant (butanol) was introduced into the solution. The precipitation was performed in 120 min a...

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