Methods and apparatuses for in situ synthesis of alloys and/or composites are disclosed, the method comprising: (a) providing an apparatus having: an electromagnetic energy source; an autofocusing scanner; a powder system; a powder delivery system; and computers coupled and configured to control the electromagnetic energy source, the autofocusing scanner, the powder system, and the powder delivery system; (b) programming the computers with structural and material specifications of the sample; (c) using the computers to control electromagnetic radiation, powder mixture, and powder deposition parameters; and (d) focusing and scanning the electromagnetic radiation onto the sample while two or more powders are concurrently deposited onto the sample to deposit layers onto the sample for multiple metal powder synthesis, metal and ceramic synthesis, ceramic synthesis, and/or gradated composition synthesis, wherein the layers comprise at least one new material which differs from the two or more powders. Other embodiments are described and claimed.

There is provided a fiber-reinforced brittle matrix composite. The fiber-reinforced brittle matrix composite comprises a brittle matrix material (for example, a cementitious or ceramics material) and a coated fiber embedded in the brittle matrix material, wherein the coated fiber comprises a fiber (for example, polyethylene fiber, glass fiber, silicon carbide fiber, alumina fiber, mullite fiber) and a coating material (for example, carbon nanofibers, carbon nanotubes), which is non-covalently disposed on the fiber. A method for producing the fiber-reinforced brittle matrix composite is also provided. The method comprises providing a fiber, disposing a coating material on the fiber to form a coated fiber, wherein the coating material is non-covalently disposed on the fiber, and embedding the coated fiber in a brittle matrix material to obtain the fiber-reinforced brittle matrix composite.

Described herein are composite materials composed of ceramic particles coated with a surfactant incorporated within a polymer matrix, methods of making same, filaments composed of the same, and articles printed using the filaments. The composite materials and articles described herein have desirable electronic and thermal properties for use in radio frequency (RF) and millimeter wave devices and demonstrate reliable performance at elevated humidity levels.

The present invention relates to a suspension comprising 50-95% by weight of the total suspension (w/w) of at least one metallic material and/or ceramic material and/or polymeric material and/or solid carbon containing material; and at least 5% by weight of the total suspension of one or more fatty acids or derivatives thereof. In addition, the invention relates to uses of such suspension in 3D printing processes.

Some variations provide a preceramic resin precursor formulation comprising: first molecules comprising at least one SiN bond and/or at least one SiC bond; and second molecules of the formula R.sub.4NCO or R.sub.4NCS, wherein R.sub.4 is a UV-active functional group. In some embodiments, R.sub.4 is selected from acrylate, methacrylate, vinyl ether, epoxide, oxetane, thiol, or a combination thereof. The first and second molecules are reacted with an isocyanate or isothiocyanate to form third molecules, providing a preceramic radiation-curable resin composition. The resin composition contains at least one SiN bond and/or at least one SiC bond in the main chain of the third molecules. Side chains of the third molecules may be selected from hydrogen, unsubstituted or substituted hydrocarbon groups, halides, esters, amines, hydroxyl, or cyano. The resin composition may be 3D printed and thermally treated to generate a ceramic material.

A process for manufacturing a composite material part includes formation of a fibrous texture from refractory ceramic fibres, placement of the fibrous texture in a mould with interposition of a filtration layer between the fibrous texture and a discharge port, the filtration layer including a partially densified fibrous structure, pressure injection of a slurry containing a powder of refractory ceramic particles into the fibrous texture, drainage by the filtration layer of the slurry solvent having passed through the fibrous texture and retention of the powder of refractory ceramic particles within the texture by the filtration layer to obtain a fibrous preform including the fibrous texture filled with refractory ceramic particles and the filtration layer, heat treatment of the refractory ceramic particles present in the fibrous texture of the preform to form a composite material part including the fibrous texture densified by a refractory ceramic matrix and the filtration layer.

The present invention relates to a suspension comprising 50-95% by weight of the total suspension (w/w) of at least one metallic material and/or ceramic material and/or polymeric material and/or solid carbon containing material; and at least 5% by weight of the total suspension of one or more fatty acids or derivatives thereof. In addition, the invention relates to uses of such suspension in 3D printing processes.

A method of preparing cerium boride powder, according to the present invention, includes a first step for generating mixed powder by mixing at least one selected from among cerium chloride (CeCl.sub.3) powder and cerium oxide (CeO.sub.2) powder, at least one selected from among magnesium hydride (MgH.sub.2) powder and magnesium (Mg) powder, and boron oxide (B.sub.2O.sub.3) powder, a second step for generating composite powder including cerium boride (Ce.sub.xB.sub.y) and at least one selected from among magnesium oxide (MgO) and magnesium chloride (MgCl.sub.2), by causing reaction in the mixed powder at room temperature based on a ball milling process, and a third step for selectively depositing cerium boride powder by dispersing the composite powder in a solution.

A method for manufacturing a part made of composite material includes injecting into a fibrous texture a slurry including at least one powder of refractory ceramic particles suspended in a liquid phase, filtering the liquid phase of the slurry and retaining the powder of refractory ceramic particles inside the texture so as to obtain a fibrous preform loaded with refractory ceramic particles, densifying the fibrous texture by treatment of the refractory ceramic particles present in the fibrous texture in order to form a refractory matrix in the texture. The method further includes, before injecting the slurry under pressure, pre-saturating the fibrous texture with a carrier fluid consisting in injecting into said texture a carrier fluid.

A method of forming a ceramic component is disclosed. A ceramic matrix material is combined with a binder material. The ceramic matrix material and the binder material are mixed to create an intermediate slurry. After mixing the ceramic matrix material and the binder material, reinforcing fibers are added to the intermediate slurry to create a final slurry. The final slurry is introduced into a mold cavity having a shape corresponding to the ceramic component. The final slurry is at least partially cured within the mold cavity to form an intermediate casting. The intermediate casting is sintered to produce the ceramic component from the intermediate casting.