On the basis of the author's methodology and structural model of monodisperse systems in combination with the theory of percolation, the parameters of the porous structure of the reaction-bound silicon nitride are estimated depending on the content of the pore-forming agent. When evaluating the thermal conductivity of ceramics, it was found that the analytical and experimental results for silicon nitride without a pore former are in satisfactory agreement with each other, and for samples with a pore former & # 8211; are several times different. A hypothesis has been put forward that a sharp decrease in thermal conductivity during the introduction of a pore-forming agent is caused by the effect of separation of silicon particles by larger particles of a pore-forming agent.
Dr. Tech. Sciences Yu. N. KRYUCHKOV (This email address is being protected from spambots. You need JavaScript enabled to view it.)
; Gzhel State University (Electroizolyator settlement, Moscow region, Russia)
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