Structure Formation,Electrophysical and Mechanical Properties of an Electrically Conducting Ceramic Composite Based on Silicon and Boron Carbides

How the structure of electrically conducting ceramic composites in the SiC B₄C system is formed has been studied. The mechanical and electrophysical properties have been investigated as a function of the ratio of the components and the sintering conditions.     

A Si3N4-ZrC resistive composite. I. Conductivity concentration dependence

Translated from Poroshkovaya Metallurgiya, No. 4(328), pp. 80–84, April, 1990.     

Effect of a ring layer filled with various substances on the eigenfrequency and Q-factor of a cylindrical quasi-optical dielectric resonator

The influence of a ring layer filled with various substances on the eigenfrequency and Q-factor of a cylindrical quasi-optical dielectric (Teflon) resonator has been investigated. The spectral and energy characteristics of an axially homogeneous whispering gallery eigenmode of this resonator are analyzed for the first time as dependent on the radius and thickness of the ring layer. It is established that the eigenfrequency behaves differently when the ring layer is filled with liquids characterized by large and small losses.     

Effect of charge composition on the structure and electrophysical properties of self-bonded silicon carbide

Computer treatment of experimental data using the method of Kriging permitted an analysis of the structure, phase composition, and electrophysical properties of silicon carbide materials produced by liquid-phase reactive sintering over a broad range of initial charge compositions. The optimal values of the electrophysical properties were determined, and the possibility of predicting the charge composition for the production of material with given electrophysical properties demonstrated.Institute of Materials Science Problems, Ukrainian Academy of Science, Kiev. Translated from Poroshkovaya Metallurgiya, Nos. 3–4, pp. 57–62, April–May, 1994.     

Dielectric characteristics of sintered silicon nitride materials

We have studied and summarized data on structure formation and dielectric characteristics of Si₃N₄-based materials obtained by hot pressing and activated sintering. We have measured the dielectric characteristics in the frequency range 1 kHz to 10 MHz. We have established that the level of the dielectric characteristics of the materials is significantly affected by the content of highly dispersed Si₃N₄ powder obtained by plasmochemical synthesis in the original mix. Translated from Poroshkovaya Metallurgiya, Nos. 3–4(412), pp. 22–26, March–April, 2000.     

Activated sintering of polydisperse silicon nitride mixtures

Data on the granulometric composition of the initial components on prepared stock have been considered and summarized. The effect of additional mechanical processing (grinding in a planetary ball mill and roller mill) on the compaction of silicon nitride materials during activated sintering have been investigated. The composition of the initial stock as well as the preparation for the production of dense ceramic silicon nitride materials have been optimized.     

Structure and electrophysigal properties of hot-pressed ceramic materials in the Si3N4-SiC system. II. Electrical conductivity of materials expressed on the basis of theories of conductivity of heterophase systems

Translated from Poroshkovaya Metallurgiya, No. 8(356), pp. 86–90, August, 1992.