Metal-ceramic/ceramic nanostructured layered composites for solid oxide fuel cells by spark plasma sintering.

In this work, bi-layered Fe-Ni-Co-YSZ/YSZ nanostructured composites for solid oxide fuel cells were obtained using the spark plasma sintering (SPS) technique. The microstructures of the anode and electrolyte were controlled by optimization of SPS consolidation parameters. The resulting bilayers have a full dense YSZ electrolyte and porous Fe-Ni-Co/YSZ anode as well as crack-free and well-bonded anode/electrolyte interface.

Spark plasma sintered Ni-YSZ/YSZ bi-layers for solid oxide fuel cell.

Ni-YSZ/YSZ bi-layers for SOFCs were fabricated by spark plasma sintering (SPS). Optimization of SPS parameters of YSZ and NiO/YSZ powders was performed in order to fabricate anode and electrolyte with desired microstructures. The effect of sintering conditions on microstructure and electrical properties of YSZ was studied.

Densification kinetics of nanocrystalline zirconia powder using microwave and spark plasma sintering--a comparative study.

Two-stage densification process of nanosized 3 mol% yttria-stabilized zirconia (3Y-SZ) polycrystalline compacts during consolidation via microwave and spark-plasma sintering have been observed. The values of activation energies obtained for microwave and spark-plasma sintering 260-275 kJ x mol(-1) are quite similar to that of conventional sintering of zirconia, suggesting that densification during initial stage is controlled by the grain-boundary diffusion mechanism. The sintering behavior during microwave sintering was significantly affected by preliminary pressing conditions, as the surface diffusion mechanism (230 kJ x mol(-1)) is active in case of cold-isostatic pressing procedure was applied.

High hardness BaCb-(BxOy/BN) composites with 3D mesh-like fine grain-boundary structure by reactive spark plasma sintering.

Boron carbide B4C powders were subject to reactive spark plasma sintering (also known as field assisted sintering, pulsed current sintering or plasma assisted sintering) under nitrogen atmosphere. For an optimum hexagonal BN (h-BN) content estimated from X-ray diffraction measurements at approximately 0.4 wt%, the as-prepared BaCb-(BxOy/BN) ceramic shows values of Berkovich and Vickers hardness of 56.

Non-catalytic facile synthesis of superhard phase of boron carbide (B13C2) nanoflakes and nanoparticles.

Boron Carbide is one the hardest and lightest material that is also relatively easier to synthesis as compared to other superhard ceramics like cubic boron nitride and diamond. However, the brittle nature of monolithic advanced ceramics material hinders its use in various engineering applications. Thus, strategies that can toughen the material are of fundamental and technological importance.

Tough yttria-stabilized zirconia ceramic by low-temperature spark plasma sintering of long-term stored nanopowders.

Weakly agglomerated 1.75 and 3 mol% yttria stabilized zirconia nanopowders were used in this study after six years of storage in vacuum-processed plastic containers. The proper storage conditions of the Y-TZP nanopowders avoided the hard agglomeration.

'Beautiful' unconventional synthesis and processing technologies of superconductors and some other materials.

Superconducting materials have contributed significantly to the development of modern materials science and engineering. Specific technological solutions for their synthesis and processing helped in understanding the principles and approaches to the design, fabrication and application of many other materials. In this review, we explore the bidirectional relationship between the general and particular synthesis concepts.

Zirconia nanoceramic via redispersion of highly agglomerated nanopowder and spark plasma sintering.

A 2.7 mol% yttria stabilizing tetragonal zirconia (2.7Y-TZP) nanopowder was synthesized and stored for five years.

Si3N4-TiN nanocomposite by nitration of TiSi2 and consolidation by hot pressing and spark plasma sintering.

Homogeneous nanostructured Si3N4-TiN composite powder was obtained by nitration of a TiSi2 powder precursor in a nitrogen flow. Mechanoactivation of titanium disilicide increases the nitration rate and reduces the temperature of formation of the Si3N4 and TiN. The properties of hot pressing (HP) and spark plasma sintering (SPS) of the nanostructured Si3N4-TiN composite with Y2O3 and Al2O3 additives have been studied.

Nanoblast synthesis and consolidation of (La0.8Sr0.2)(Ga0.9Mg0.1)O(3-delta) under Spark plasma sintering conditions.

Four-cation nanograined strontium and magnesium doped lanthanum gallate (La0.8Sr0.2) (Ga0.

Multiple nano-blast synthesis of PT/8Y-ZP composite nanopowders.

We demonstrate a processing technique based on the synthesis of ceramic nanopowders and simultaneous impregnation with metallic nanoparticles by multiple 'nano-blasts' of embeded cyclotrimethylene trinitramine in preliminary engineered multi-component nano-reactors. 'Nano-blasts' of impregnated cyclotrimethylene trinitramine deagglomerate the nanopowder due to the high energetic impacts of the blast waves, while the decomposition of compounds and their solid-solubility is enhanced by the extremely high local temperature generated during the nano-explosions. We applied this technique to produce nanosized agglomerate-free 8 mol% yttria-doped cubic zirconia aggregates with an average size of 53 nm impregnated with 10 mass% of platinum particles of 2-14 nm.

Nanoexplosion synthesis of multimetal oxide ceramic nanopowders.

Herein we demonstrate a unique processing technique for engineering multicomponent ceramic nanopowders with precise morphologies by "nanoblast" calcination/deagglomeration. Multiple "nanoexplosions" of C(3)H(6)N(6)O(6) nanoparticles embedded in preliminary engineered nanoreactors break apart the agglomerates because of the highly energetic impacts of the blast waves. Also, the solid-solubility of one component into the other is enhanced by the extremely high local temperature generated during the nanoexplosions.