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The production of finely dispersed yttrium-aluminum garnet (YAG) powder, which is the initial material for ceramics, using as precursors secondary aluminum butylate and a crystal-hydrate salt -yttrium chloride hexahydrate, is examined. It is found that depending on the conditions of synthesis and temperature solid products of different forms are formed. The conditions for synthesizing the crystalline phase of YAG by heat-treatment of the precipitates obtained at temperature ³ 900°C are determined.On account of its optical and thermo-mechanical properties yttrium-aluminum garnet (YAG) is widely used as a crystal base for making many laser materials. The structure of YAG makes it possible to introduce diverse rare-earth ions and iron-group ions as dopants into it.The most widely used method of obtaining a YAG mix for growing single crystals is solid-phase synthesis. The YAG mix is also obtained by precipitation in the form of oxalates, carbonates, and hydroxides followed by treatment at high temperatures. The method of "freezing out" (cryochemical method) and self-propagating high-temperature synthesis are used less often. The sol -gel method is one of the methods being actively developed in recent years for obtaining the YAG mix [1]. At the same time the use of such mixes in complicated and expensive methods for growing refractory crystals from melt does not always give the required optical quality and perfection of laser materials.The successful realization of a YAG : Nd laser with an active element consisting of transparent ceramic showed real prospects for obtaining a laser ceramic. A highly transparent ceramic YAG : Nd with large size and optical quality exceeding that of the corresponding single crystals was synthesized in [2]. Lasers with active elements consisting of such a ceramic make it possible to obtain record high power, reaching many tens of kilowatts [3].The development of an ultradispersed materials technology using the sol -gel method [4, 5] is of special interest for making highly transparent laser ceramic. The fundamental achievement of this technology lies in the possibility of monitoring the interphase surface of the material at a very early stage of its production and creating a unique homogeneous structure or structures with an ultradisperse phase [6]. The main advantages of the sol -gel technology as compared with other methods are the more uniform distribution of additives, higher dispersity of the powders obtained, and others. The distribution of the precursors in the porous matrix when using the sol -gel method for synthesis of disperse systems creates an effective barrier for agglomeration processes and makes it possible to maintain nanosize particles in a high-temperature processing regime. As a rule the materials and articles obtained are of higher quality as compared with materials fabricated by other methods [4,5,7].Our work is devoted to an investigation of the production of nanostructured YAG powder by a hybrid sol -gel method using a solution of secondary aluminum butylate (SAB) ...

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