Silicon-carbon composite materials and related processes are disclosed that overcome the challenges for providing amorphous nano-sized silicon entrained within porous carbon. Compared to other, inferior materials and processes described in the prior art, the materials and processes disclosed herein find superior utility in various applications, including energy storage devices such as lithium ion batteries.

The present invention relates to a method for preparing a SiC—Si.sub.3N.sub.4 composite material and a SiC—Si.sub.3N.sub.4 composite material prepared according to same and comprises the steps of: preparing a mold; and forming a SiC—Si.sub.3N.sub.4 composite material by introducing, to the mold, a source gas comprising Si, N and C, at 1100 to 1600° C. More particularly, the present invention provides the SiC—Si.sub.3N.sub.4 composite material of high purity that is applicable to a semiconductor process, and increases the thermal shock strength of a SiC material by causing Si.sub.3N.sub.4, which is a material with a high thermal shock strength, to grow together via a CVD method.

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.

A molding tool made of carbon or graphite, namely a casting mold or a casting core for the processing of molten metal or to a molding tool for the processing of molten glass, such as for example a blow mold and a method for producing the molding tool.

A method for producing carbon or graphite foam parts with high purity level for high-temperature insulation under vacuum or protective gas, as insulating material or as filter material, includes the following steps: introducing dry, foamable starch (1) into an open-top container (2) having a round or angular cross section, until the base (3) of the container (2) is covered amply and uniformly with starch (1); introducing the container (2) partly filled with starch (1) into an oven (4), and heating the container (2) to a foaming temperature of >180° C. over a prolonged period of several hours to foam the starch (1), until the container (2) has filled completely with carbon foam (6); withdrawing the container (2) from the oven (4) and extracting the carbon foam (6) after sufficient cooling, and optionally portioning the carbon foam (6) into carbon foam parts (6.1).

Methods of forming a ceramic matrix, as well as fiber preforms and methods of forming fiber preforms to facilitate formation of a ceramic matrix are provided. The method includes obtaining a fiber preform to facilitate forming the ceramic matrix. The fiber preform includes a fiber layer with a plurality of fibers and a heating element embedded within the fiber preform. The method also includes heating the fiber preform via the heating element embedded within the fiber preform, and depositing matrix material into the fiber preform by embedded wire chemical vapor deposition (EWCVD) of the matrix material during the heating of the fiber preform by the heating element. The chemical vapor deposition of the matrix material within the fiber preform facilitates formation of the ceramic matrix.

A method of forming a ceramic matrix composite component with cooling channels includes embedding a plurality of wires into a preform structure, densifying the preform structure with embedded wires, and removing the plurality of wires to create a plurality of corresponding channels within the densified structure.

A method for manufacturing a C/C part includes fabricating an oxidized PAN fiber preform comprising a stack of sheets of multi-axial, non-crimp, OPF fabric. The method includes positioning the oxidized PAN fiber preform with a female forming tool, the female forming tool comprising a die recess, and forming the oxidized PAN fiber preform into a shaped body. The shaped body is removed from the female forming tool and moved into a graphite fixture for carbonization. The carbonized shaped body may also be densified into the final C/C part. The carbonized shaped body can also be placed in a perforated graphite fixture for densification and removed from the perforated graphite fixture between densification processes for machining and for facilitating further densification.

A shape forming tool for pre-carbonization compression of a fibrous preform is provided, comprising a female forming tool, a first plug, a second plug, and a wedge, each configured to be received by a die recess of the female forming tool. A first tapered surface of the wedge is configured to engage the first plug and the second tapered surface of the wedge is configured to engage the second plug. In response to the first tapered surface of the wedge engaging the first plug and the second tapered surface of the wedge engaging the second plug, the first plug and the second plug, respectively, are configured to move laterally towards opposing sides of the female forming tool and/or vertically toward a bottom side of the female forming tool to compress the fibrous preform into a shaped body.

A single stage OPF-to-carbon preform shape forming method includes positioning an oxidized PAN fiber preform with a female forming tool, positioning a vacuum bag over the oxidized PAN fiber preform, and vacuum forming the oxidized PAN fiber preform into a shaped body. The vacuum formed shaped body (while still in the shape forming fixture) may be loaded into a carbonization furnace and carbonized. The vacuum bag may be burned away in the carbonization furnace during carbonization.