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Three-layered ceramic membranes based on stabilized zirconia for planar solid-oxide fuel cell (SOFC) are prepared by the tape casting method. The outer layers containing 94 mol % ZrO2–6 mol % Sc2O3 provide the enhanced mechanical stability; the inner layer has the composition of 89 mol % ZrO2–10 mol % Sc2O3–1 mol % Y2O3 which has the highest anionic conductivity in the series of solid solutions ZrO2–Y2O3–Sc2O3. Studying the mechanical characteristics shows that the ultimate strength (bending strength) of these membranes much exceeds the value typical of single-layered samples. The anionic conductivity of three-layered ceramics is studied by the impedance spectroscopy in the frequency range from 1Hz to 1 MHz. Membrane-electrode assemblies for SOFCs are fabricated and their electrochemical properties are studied under the conditions of fuel cell operation.

This article describes the process of firing aluminum nitride substrates, which is a process that occurs under its characteristic conditions: high temperatures of over 1800°C and a reducing environment. This article also presents the fact that high quality substrates having desirable properties such as high thermal conductivity and parallelism between layers can be achieved. This article also describes how optimal firing modes can be established using a special sagger design based on boron nitride. The designed sagger is a container that consists of a body, which is a rectangular box; a bottom; and plane–parallel separating plates with supports. To create a local (inside the sagger) clean recovery medium, mortise and tenon joints that interlock are provided between the body and bottom and the interlocks are filled with a heat-resistant inert powder.

Results obtained in a study of the process of synthesis of a polydisperse boron carbide powder (average particle size 2.10 µm) characterized by a broad particle size distribution are presented. The process in which a ceramic is produced from the thus synthesized boron carbide by hot compaction was also analyzed. In some cases, a sintering additive, highly dispersed chromium carbide powder (average particle size 7.13 µm), was used. The hot compaction was performed in argon at moderate parameters: pressure 35 MPa and temperature 1950°C. The porosity and water-absorption capacity of the samples obtained are very low and do not exceed 0.02%. The average values of the bending and compression strengths were 406 and 1553 MPa, respectively. A microhardness of about 42 GPa was reached in sintering of boron carbide. The microhardness in sintering of boron carbide with addition of chromium carbide was 45–46 GPa.

Mechanical strength and microstructure of the anode supports are among the most critical factors affecting the long-term stability and performance of the intermediate-temperature solid oxide fuel cells (IT-SOFCs). In this work, the anode supports made of Ni/NiO and 10 mol.% Sc2O3 and 1 mol.% Y2O3 co-stabilized zirconia (10Sc1YSZ) were fabricated by tape casting, followed by sintering and screen-printing of the anode functional layer of 10 mol.% Gd2O3 doped ceria (10GDC) and NiO. Then two dense solid-electrolyte layers, 8 mol.% Y2O3 stabilized zirconia (8YSZ) and 10GDC, were deposited by the reactive pulsed dual magnetron sputtering. Mechanical properties of as-sintered and reduced anode supports were estimated employing three-point bending technique. The power density of model anode-supported SOFCs, where mechanical stability of the support was kept after complete reduction in hydrogen, achieved 0.3 W/cm2 at 800°C and 0.6 V under air/hydrogen gradient.

Bilayered substrates for anode-supported solid oxide fuel cells (SOFCs), made of NiO and 10 mol.% Sc2O3 and 1 mol.% Y2O3 co-stabilized zirconia (10Sc1YSZ), were produced employing the tape casting technique. The optimization of the pore former (rice starch) content in the starting suspension and thermal treatment conditions provide necessary porosity, simultaneously maintaining sufficiently high mechanical strength of the composite measured by the three-point bending method. Bilayered gas-tight solid electrolyte films of 8 mol.% Y2O3 stabilized zirconia and 10 mol.% Gd2O3 doped ceria (8YSZ/10GDC) were deposited by magnetron sputtering, followed by annealing at 1200 °C. The area-specific power density of a model SOFC achieved 1.8, 1.4, and 0.9 W/cm2 at 800, 750, and 700 °C, respectively.

The paper presents the results of research and development of cold gas-dynamic spray regimes for production of copper coatings on ceramic substrates. Samples with a topological pattern of coating were obtained and their primary diagnostics was carried out. In particular, it is shown that the samples obtained can withstand thermal cycling (more than 100 cycles) in the temperature range from -60 to +150 °C.

Results of studies of solid-electrolyte membranes with the composition of 89 mol % ZrO2-10 mol % Sc2O3-1 mol % CeO2 obtained using the technique of slip casting on a moving tape are presented. Optimization of technological parameters of membrane casting and sintering allowed manufacturing parallel plane gastight plates with the thickness of 200–250 μm that were tested in model solid oxide fuel cells (SOFC) of planar design with standard electrodes based on nickel-containing cermets and lanthanum-strontium manganite. It is shown that though conductivity of such membranes is lower as compared to that of compacted and sintered compacted samples due to diffusion of the aluminum oxide admixture in the course of the manufacturing process, power density of SOFC is sufficiently high and reaches 430 mW/cm2 at 850°C.

The effect of dry axial compaction process parameters on physicomechanical properties of ceramic composite material ZTA (Al2O3–ZrO2, ZrO2 > 20 wt.%) with a different content of nanosize ZrO2 powder (range 0 – 4 wt.%) is studied. The dependence of compact density is determined, and also the main physicomechanical properties of sintered specimens on compaction conditions, and linear specimen shrinkage on compaction pressure in the pressing direction and radial direction. It is revealed that an increase in the amount of nanosize ZrO2 in an original charge facilitates an increase in compact and sintered specimen density, and a reduction in specimen linear shrinkage during firing. Comparative evaluation is carried out under industrial production conditions for wear resistance of ceramic specimens based on Al2O3 and ZrO2 with a different ZrO2 content, and also addition of nanosize ZrO2.

Results of a study of elements of solid-state electronics by holographic interferometry are presented. Examples of measurement of thermal strains of real products and control of engineering processes in the production of static induction transistors (SITs) and ultra-high frequency hybrid integrated circuits are given.