A highly oriented nanometer MAX phase ceramic and a preparation method for a MAX phase in-situ autogenous oxide nanocomposite ceramic. The raw materials comprise a MAX phase ceramic nano-lamellar powder body or a blank body formed by the nano-lamellar powder body, wherein MAX phase ceramic nano-lamellar particles in the powder body or the blank meet the particle size being between 20-400 nm, and the oxygen content is between 0.0001%-20% by mass; MAX phase grains in the ceramic obtained after the raw materials are sintered are lamellar or spindle-shaped, the lamellar structure having a high degree of orientation. Utilizing special properties of the nano-lamellar MAX powder body, orientation occurs during compression and deformation to obtain a lamellar structure similar to that in a natural pearl shell, and such a structure has a high bearing capacity and resistance to external loads and crack propagation, just like a brick used in a building.

The invention relates to hydrocarbon conversion, to equipment and materials useful for hydrocarbon conversion, and to processes for carrying out hydrocarbon conversion, e.g., hydrocarbon pyrolysis processes. The hydrocarbon conversion is carried out in a reactor which includes at least one channeled member that comprises refractory and has an open frontal area≤55%. The refractory can include non-oxide ceramic.

A method for sintering metallic and/or non-oxide components includes completely encapsulating, in a metal halide salt, a green body comprising at least one metallic and/or non-oxide powder, and compressing the encapsulated green body so as to be gastight. The method further includes heating, together with a metal halide salt in the presence of oxygen up to sintering temperatures, the compressed, encapsulated green body. The method additionally includes at least partially dissolving, after cooling, the metal halide salt in a liquid so that the sintered component can be removed.

The sintered material includes a powder-derived material containing one or both of a nitride and an oxynitride, each of which contains at least one first metal element selected from the group consisting of group 4 elements, group 5 elements and group 6 elements in the periodic table, the rate y1/x1 of the atomic ratio y1 of non-metal element atoms in the powder-derived material to the atomic ratio x1 of metal element atoms therein is greater than 1, and the powder-derived material has a cubic structure.

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.

An article includes a MAX phase solid and a high temperature melting point metallic material interdispersed with the MAX phase material.

For the first time, components can be produced from MAX-phases due to the use of an additive production method. A method for producing a component from MAX phases, in particular from Ti.sub.3SiC.sub.2 and/or Cr.sub.2AlC, in which an additive manufacturing process is disclosed. Powder is applied layer by layer and densified, the grain sizes of the powder lying at 10 m to 60 m, in which the scanning speed between the energy beam of the laser or electron beam and substrate with powder lies between 400 mm/s and 2000 mm/s, in particular at 1000 mm/s to 1500 mm/s, in which the power output is between 80 W and 250 W, in particular is 100 W to 170 W, in which a spot size of the energy beam lies between 30 m and 300 m.

Provided are: composite particles having excellent oxidation resistance; and a method for producing composite particles. The composite particles are obtained by forming a composite of TiC and at least one of Zr and Si. In the method for producing composite particles, a titanium oxide powder and at least one of a zirconium oxide powder and a silicon oxide powder are used as raw material powders, and composite particles are produced using a gas phase method.

Pre-ceramic particle solutions can prepared by a Coordinated-PDC process, a Direct-PDC process or a Coordinated-Direct-PDC process. The pre-ceramic particle solution includes a polymer selected from the group consisting of (i) an organic polymer including a metal or metalloid cation, (ii) a first organometallic polymer and (iii) a second organometallic polymer including a metal or metalloid cation different from a metal in the second organometallic polymer, a plurality of particles selected from the group consisting of (a) a ceramic fuel particle and (b) a moderator particle, a dispersant, and a polymerization initiator. The pre-ceramic particle solution can be supplied to an additive manufacturing process, such as digital light projection, and made into a structure (which is pre-ceramic particle green body) that can then be debinded to form a polymer-derived ceramic sintered body. In some embodiments, the polymer-derived ceramic sintered body is a component or structure for fission reactors.

A method of fabricating a ceramic material, the method including forming a ceramic material by performing a first chemical reaction at least between a first powder of an intermetallic compound and a reactive gas phase, a liquid phase being present around the grains of the first powder during the first chemical reaction, the liquid gas phase being obtained from a second powder of a metallic compound by melting the second powder or as a result of a second chemical reaction between at least one element of the first powder and at least one metallic element of the second powder, a working temperature being imposed during the formation of the ceramic material, which temperature is low enough to avoid melting the first powder.