An additive manufacturing (AM) system includes a housing defining a chamber, a build platform disposed in the chamber at a first elevation, and a lower gas inlet disposed at a second elevation and configured to supply a lower gas flow. The AM system includes a contoured surface extending between the lower gas inlet and the build platform to direct the lower gas flow from the second elevation at the lower gas inlet to the first elevation at the build platform, where the contoured surface discharges the lower gas flow in a direction substantially parallel to the build platform. The AM system also includes one or more gas delivery devices coupled to the lower gas inlet to regulate one or more flow characteristics of the lower gas flow, and a gas outlet configured to discharge the lower gas flow.

A chemical vapor infiltration (CVI) method for densifying at least one porous component includes placing the at least one porous component inside a crucible, bringing temperature inside the crucible to a value adapted to densify the porous component to transform it into a densified component, bringing pressure inside the crucible between 0.1 KPa and 25 KPa, once operational temperature and pressure are reached, flowing gas inside the crucible, gas being suitable for densifying the porous component to transform it into a densified component, and keeping an oxidizing environment outside the crucible, the external environment lapping against the crucible. The crucible is provided of at least one material having thermal conductivity greater than 30 W/mK from room temperature to at least 1000° C. selected from: sintered silicon carbide (SiC), silicon-infiltrated silicon carbide (Si—SiC), sintered boron carbide (B4C), silicon-infiltrated boron carbide (Si—B4C), sintered zirconium carbide (ZrC), silicon-infiltrated zirconium carbide (Si—ZrC), a combination of silicon carbide (SiC), boron carbide (B4C) and sintered and/or silicon-infiltrated zirconium carbide (ZrC).

A method of manufacture for a carbon/carbon part including a method to remove contamination from an intermediate product of the carbon/carbon part and furnace utilizing a gaseous reducing agent hydrogen gas to reduce the contaminates, thereby causing the contaminates to transition to a gaseous state at relatively lower temperatures. A method to remove contamination from an intermediate product of the carbon/carbon part and furnace utilizing hydrogen gas to reduce the contaminates, thereby causing the contaminates to transition to a gaseous state at relatively lower temperatures.

A dielectric material includes a main component represented by (Ba.sub.1-xCa.sub.x)(Ti.sub.1-y(Zr, Sn, Hf).sub.y)O.sub.3 (0≤x≤1 and 0≤y≤0.5); a first subcomponent including at least one of elements among Y, Dy, Ho, Er, Gd, Ce, Nd, Nb, Sm, Tb, Eu, Tm, La, Lu, and Yb; a second subcomponent including Si and/or Al; and a third subcomponent including Ba and/or Ca.

The present disclosure provides a composite including a nitride sintered body having a porous structure and a semi-cured product of a heat-curable composition impregnated into the nitride sintered body, wherein a dielectric breakdown voltage obtainable after disposing the composite between adherends, heating and pressurizing the composite for 5 minutes under the conditions of 200° C. and 10 MPa, and further heating the composite for 2 hours under the conditions of 200° C. and atmospheric pressure, is greater than 5 kV.

A sintered body containing polycrystalline grains of a metal oxynitride containing at least two metal elements, wherein Ba and at least one metal element of a crystal phase of the sintered body are contained in a triple point that is not a void between the polycrystalline grains. A method for producing the sintered body includes sintering a mixture of at least a metal oxynitride as a main component and a sintering aid containing cyanamide in an atmosphere containing nitrogen or a rare gas or in a reduced-pressure atmosphere of 10 Pa or less while applying a mechanical pressure with a retention time at a maximum heating temperature during the sintering set to 1 minute to 10 minutes.

Disclosed are a dielectric ceramic includes a plurality of crystal grain bulks including a ceramic, and a grain boundary between the plurality of crystal grain bulks, wherein a dopant is segregated in the grain boundary.

A ceramic composite sintered body, including: a metal oxide as a main phase, and silicon carbide as a sub-phase, in which crystal grains of the silicon carbide are dispersed in crystal grains of the metal oxide and at crystal grain boundaries of the metal oxide, and an average crystal grain size of the silicon carbide dispersed at the crystal grain boundaries of the metal oxide is 0.30 μm or less.

A sintered oxide includes an In.sub.2O.sub.3 crystal, and a crystal A whose diffraction peak is in an incidence angle (2θ) range defined by (A) to (F) below as measured by X-ray (Cu-K α ray) diffraction measurement: 31.0 to 34.0 degrees . . . (A); 36.0 to 39.0 degrees . . . (B); 50.0 to 54.0 degrees . . . (C); 53.0 to 57.0 degrees . . . (D); 9.0 to 11.0 degrees . . . (E); and 19.0 to 21.0 degrees . . . (F).

Provided is a method for producing a calcium carbonate sintered body whereby a good sintered body can be obtained without having to use any sintering aid. A method for producing a calcium carbonate sintered body includes the steps of: compacting calcium carbonate to make a green body; heating the green body under a condition of a temperature of 500° C. or lower to remove an organic component contained in the green body; and sintering the green body under conditions of a carbon dioxide atmosphere and a temperature of 450° C. or higher to obtain a calcium carbonate sintered body.