A method to form a machinable ceramic matrix composite comprises forming a porous ceramic multilayer on a surface of a fiber preform. In one example, the porous ceramic multilayer comprises a gradient in porosity in a direction normal to the surface. In another example, the porous ceramic multilayer includes low-wettability particles having a high contact angle with molten silicon, where an amount of the low-wettability particles in the porous ceramic multilayer varies in a direction normal to the surface. After forming the porous ceramic multilayer, the fiber preform is infiltrated with a melt, and the melt is cooled to form a ceramic matrix composite with a surface coating thereon. An outer portion of the surface coating is more readily machinable than an inner portion of the surface coating. The outer portion of the surface coating is machined to form a ceramic matrix composite having a machined surface with a predetermined surface finish and/or dimensional tolerance.

The present application discloses and claims a method to make a flexible ceramic fibers (Flexiramics™) and polymer composites. The resulting composite has an improved mechanical strength (tensile) when compared with the Flexiramics™ respective the nanofibers alone. Additionally a composite has better properties than the polymer alone such as lower fire retardancy, higher thermal conductivity and lower thermal expansion. Several different polymers can be used, both thermosets and thermoplastics. Flexiramics™ has unique physical characteristic and the composite materials can be used for numerous industrial and laboratory applications.

Improved formulations of an interface material are described. These formulations may, in at least some cases, match and/or accommodate dimensional changes in the part and/or support structure throughout thermal processing (e.g., debind and sintering, or sintering only). Furthermore, these formulations may also maintain the property of resisting bonding between the interface and the part and/or support structure while also maintaining a physical separation between the part and support structure. In some cases, an improved interface material may accommodate strain associated with the shrinkage of a part (and optionally support structure) during sintering while also minimally impacting the ability of the part (and optionally support structure) to shrink or otherwise change in dimension. In some cases, the interface material may include one or more fugitive phases that are removed during thermal processing (e.g., through pyrolysis of the fugitive phase(s)).

A melt-deposition additive composition including, based on the total weight of the composition, from 75 to 90.75% by weight of at least one inorganic material, and a polymer phase including: from 9 to 20% by weight of at least one thermoplastic elastomer, from 0.25 to 5% by weight of at least one low density polyethylene, from 0 to 5% by weight of at least one polyethylene glycol having a molar mass of from 5,000 to 20,000 g/mol, and from 0 to 3% by weight of polyethylene terephthalate, preferably glycol, for use in a melt-deposition additive manufacturing process. A method for the preparation of a 3D article using this composition, the article obtained comprising at least 99% by weight of inorganic material(s) with respect to the total weight of the article and uses of this article.

A graphite-containing refractory has higher bending strength and fracture energy than known refractories. The graphite-containing refractory has a graphite content of 1% to 80% by mass. 1000 to 300000 carbon fibers with a fiber diameter of 1 to 45 μm/fiber are bundled. The carbon fiber bundle has a length of 100 mm or more and is placed within the graphite-containing refractory to form the same.

A method of producing a graphite-containing refractory within which carbon fiber bundles are placed, the graphite constituting 1% to 80% by mass, the method including a bundling step of bundling carbon fibers to form the carbon fiber bundles; a mixing step of mixing a refractory raw material with graphite to prepare a graphite-containing refractory raw material; a pressing step of pressing the graphite-containing refractory raw material in which the carbon fiber bundles are placed to prepare a formed product; and a drying step of drying the pressed product, wherein the bundling step includes bundling 1000 to 300000 of the carbon fibers with a fiber diameter of 1 to 45 μm/fiber to form carbon fiber bundles 100 mm or more in length.

Described herein are cold-sintered ceramic polymer composites and processes for making them from ceramic precursor materials and monomers and/or oligomers. The cold sintering process and wide variety of monomers permit the incorporation of diverse polymeric materials into the ceramic.

A method of fabricating a composite part, includes forming a fiber preform for the part that is to be obtained by depositing a plurality of fiber structures impregnated with a thermoplastic polymer onto a surface, with deposition being performed by automated fiber placement; eliminating the thermoplastic polymer present in the preform by dissolution with a solvent; and injecting a liquid impregnation composition into the pores of the fiber preform after eliminating the thermoplastic polymer in order to form a matrix in the pores of the fiber preform.

An installation for depositing a shaped filled roving intended to be used to manufacture a composite-material component, includes a device for feeding a fibrous roving impregnated with a composition including a binder and ceramic or carbon fillers, a die for shaping and draining the binder defined by at least one porous surface, the die having an evolving section between an inlet section and an outlet section, the inlet section being larger than the outlet section, a support in communication with the die outlet on which the shaped roving is to be deposited, and a first conveying device configured to convey the roving from the feed device through the die and to the support.

A method for producing a three-dimensional object, the method including: disposing powder; disposing fibers; and applying liquid for binding the powder and the fibers to at least one selected from the group consisting of the powder and the fibers.