An embodiment of a PCD insert comprises an embodiment of a PCD element joined to a cemented carbide substrate at an interface. The PCD element has internal diamond surfaces defining interstices between them. The PCD element comprises a masked or passivated region and an unmasked or unpassivated region, the unmasked or unpassivated region defining a boundary with the substrate, the boundary being the interface. At least some of the internal diamond surfaces of the masked or passivated region contact a mask or passivation medium, and some or all of the interstices of the masked or passivated region and of the unmasked or unpassivated region are at least partially filled with an infiltrant material.

A ceramic matrix composite includes a substrate which contains a fibrous body made of silicon carbide fiber, and a matrix which is formed in the substrate, and which contains silicon carbide and a silicon material made of silicon or a binary silicon alloy.

A coating fabrication method includes providing engineered granules and thermally consolidating the engineered granules on a substrate to form a silicate-resistant barrier coating. Each of the engineered granules is an aggregate of at least one refractory matrix region and at least one calcium aluminosilicate additive region (CAS additive region) attached with the at least one refractory matrix region. In the thermal consolidation, the refractory matrix region from the engineered granules form grains of a refractory matrix of the silicate-resistant barrier coating and the CAS additive region from the engineered granules form CAS additives that are dispersed in grain boundaries between the grains.

Polysilocarb formulations, cured and pyrolized materials, was well as articles and use for this material. In particular pyrolized polysilocarb ceramic materials and articles contain these materials where, the ceramic has from about 30 weight % to about 60 weight % silicon, from about 5 weight % to about 40 weight % oxygen, and from about 3 weight % to about 35 weight % carbon, and wherein 20 weight % to 80 weight % of the carbon is silicon-bound-carbon and 80 weight % to about 20 weight % of the carbon is free carbon.

Nanocomposite silicon and carbon compositions. These compositions can be made from polymer derived ceramics, and in particular, polysilocarb precursors. The nanocomposite can have non-voids or be nano-void free and can form larger macro-structures and macro-composite structures. The nanocomposite can contain free carbon domains in an amorphous SiOC matrix.

A ceramic porous body including: skeleton portions including an aggregate and at least one bonding material; and pore portions formed between the skeleton portions, the pore portions being capable of allowing a fluid to flow therethrough, wherein the pore portions have a pore volume ratio of pores having a pore diameter of from 10 to 15 μm, of from 4 to 17%.

Disclosed herein is a chemical vapor infiltration method including flowing ceramic precursors through a preform and depositing a matrix material on the preform at a first gas infiltration pressure, increasing the gas filtration pressure to a second gas infiltration pressure, and lowering the gas infiltration pressure to a third gas infiltration pressure which is intermediate to the first and second gas infiltration pressures.

The invention relates to a method for producing a non-oxide ceramic powder comprising a nitride, a carbide, a boride or at least one MAX phase with the general composition Mn+1AXn, where M=at least one element from the group of transition elements (Sc, Ti, V, Cr, Zr, Nb, Mo, Hf and Ta), A=at least one A group element from the group (Si, Al, Ga, Ge, As, Cd, In, Sn, Tl and Pb), X=carbon (C) and/or nitrogen (N) and/or boron (B), and n=1, 2 or 3. According to the invention, corresponding quantities of elementary starting materials or other precursors are mixed with at least one metal halide salt (NZ), compressed (pellet), and heated for synthesis with a metal halide salt (NZ). The compressed pellet is first enveloped with another metal halide salt, compressed again, arranged in a salt bath and heated therewith until the melting temperature of the salt is exceeded. Optionally, melted silicate can be added, which prevents the salt from evaporating at high temperatures. Advantageously, the method can be carried out in the presence of air.

A module and a process for forming a monolithic substantially closed-porosity silicon carbide fluidic module having a tortuous fluid passage extending through the module, the tortuous fluid passage having an interior surface, the interior surface having a surface roughness in the range of from 0.1 to 10 μm Ra. The process includes positioning a positive fluid passage mold within a volume of silicon carbide powder, the powder coated with a binder; pressing the volume of silicon carbide powder with the mold inside to form a pressed body; heating the pressed body to remove the mold; and sintering the pressed body.

An article includes a ceramic-based substrate and a barrier layer on the ceramic-based substrate. The barrier layer includes a matrix of barium-magnesium alumino-silicate or SiO.sub.2, a dispersion of silicon oxycarbide particles in the matrix, and a dispersion of particles, of the other of barium-magnesium alumino-silicate or SiO.sub.2, in the matrix.