Characteristics are considered for material prepared by cryochemical technology connected with its thermal conductivity and heat capacity, i.e., heat penetration coefficient. It is concluded that for rapidly occurring solidification it is desirable to use in calculations not the temperature of the cooling medium or substrate, but the contact temperature of interacting media, and this increases calculation accuracy. The effect of cooling rate with evaporation freezing of aqueous salt solutions of nickel, zinc, manganese and iron sulfate systems that are the starting material in the production of Ni-Zn and Mn-Zn ferrites, and also the properties of the salt and oxide powders obtained are studied. It is shown that under these conditions an effect arises of concentration supercooling of liquid, i.e., formation close to the phase transformation front of a region of supersaturated and supercooled solution that gives rise to loss of stability for the phase interface. The effect of cooling rate and frequency on material fineness and micro structure is analyzed. Features are demonstrated of solidification in a vacuum compared with other freezing methods.
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