A cutting tool (1) formed of a silicon nitride-based sintered body (2) including a matrix phase (3), a hard phase (4), and a grain boundary phase (10) in which a glass phase (11) and a crystal phase (12) exist. The sintered body (2) contains yttrium in an amount of 5.0 wt % to 15.0 wt % in terms of an oxide, and contains titanium nitride as the hard phase (4) in an amount of 5.0 wt % to 25.0 wt %. In an X-ray diffraction peak, a halo pattern appears at 2θ ranging from 25° to 35° in an internal region of the sintered body (2). A ratio B/A of a maximum peak intensity B to a maximum peak intensity A satisfies 0.11≤B/A≤0.40 . . . Expression (1) in a surface region of the sintered body (2), and satisfies 0.00≤B/A≤0.10 . . . Expression (2) in the internal region of the sintered body (2).

The invention provides filamentous organism-derived carbonaceous materials doped with organic and/or inorganic compounds, and methods of making the same. In certain embodiments, these carbonaceous materials are used as electrodes in solid state batteries and/or lithium-ion batteries. In another aspect, these carbonaceous materials are used as a catalyst, catalyst support, adsorbent, filter and/or other carbon-based material or adsorbent. In yet another aspect, the invention provides battery devices incorporating the carbonaceous electrode materials.

The present invention provides means capable of imparting high temporal stability to a hardening aid solution which serves as a raw material and capable of imparting high strength and high quality stability to a hardened body of the self-hardening material, in the hardened body of the self-hardening material that contains a ceramic powder containing Si element at least on the surface thereof. The present invention relates to a hardening aid solution containing Si element, an alkali, and a dispersing medium, wherein the dispersing medium contains water; a dissolution concentration of the Si element is 20000 mass ppm or more; the number of moles of the alkali present in 1 kg of the dispersing medium is 2 mol/kg or more; an absolute value of an amount of change in a dissolution concentration of Si element in a solution obtained by diluting the hardening aid solution by 2 times based on the mass using an aqueous KOH solution having a concentration of 3 mol/L is 2000 mass ppm or less, between before and after a heat dissolution test including heating the solution at a solution temperature of 80° C. for 5 hours, and then allowing the solution to stand in an ambient environment at 25° C. for 1 hour; and the hardening aid solution is used for hardening a powder containing a ceramic powder containing Si element at least on the surface thereof.

The present invention relates to the field of new materials technology, in particular to carbon nitride composite ceramic tool materials, preparation method and cutting tools thereof. The raw materials comprise carbon nitride, titanium carbonitride, molybdenum, nickel and cobalt, carbon nitride as the matrix phase, titanium carbonitride as the reinforcing phase are added to the carbon nitride based composite ceramic materials, with molybdenum, nickel and cobalt as a suitable sintering aid, dense composite tool material is obtained with vacuum hot press sintering method. The prepared carbon nitride based composite ceramic tool materials boast the advantages of low cost, high hardness, high bending strength and high fracture toughness, which is an important way to promote the innovation, development and popularization of carbon nitride materials.

A method for manufacturing a ceramic substrate by a 3D-printing process is described. The method comprises operating a 3D-printer to print a green-state ceramic body having a height extending to spaced apart first and second end surfaces and at least one via extending at least part-way along the height of the green-state ceramic body from the first end surface toward the second end surface. Then, the green-state ceramic body is sintered to provide the ceramic substrate with the at least one via. In cross-section, the at least one via has a square-shaped via with rounded corners.

A functionally graded firing setter that includes a substrate layer of cubic oxide; a top layer of unstabilized zirconium dioxide/hafnium dioxide; and a continuous transitional gradient layer disposed between the substrate layer and the top layer. The continuous transitional gradient layer includes cubic oxide stabilized zirconium dioxide/hafnium dioxide. The cubic oxide can be calcium oxide (CaO) or magnesium oxide (MgO).

A method of preparation of a ceramic slurry for use in 3D printing includes steps of: (A) providing a plasticizer and a disperser and mixing the plasticizer and the disperser evenly; (B) mixing the mixture obtained in step (A) with an adhesive, wherein the adhesive is polyvinyl alcohol; and (C) adding a Yttria-stabilized zirconia powder to the mixture obtained in step (B) to produce, by sufficient blending and deaerating, the ceramic slurry for use in 3D printing. A method of preparation of a ceramic product includes steps of: (A) preparing a ceramic slurry with the method; (B) performing 3D printing with the ceramic slurry to form a primary green body; (C) placing the primary green body in a freezer to undergo a refrigeration process, thereby causing crystallization of polyvinyl alcohol; and (D) thawing the frozen primary green body to form a plastic green body with gel structure.

A process comprising: (i) coating particles of silicon carbide, silicon nitride, boron carbide or boron nitride with a metal alloy or metal layer; (ii) agglomerating the particles of step (i); thermally spraying the agglomerated metal or metal alloy coated particles onto a substrate to provide a coating thereon.

A method of producing polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y (Y-358) whereby powders of yttrium (III) oxide, a barium (II) salt, and copper (II) oxide are pelletized, calcined at 850 to 950° C. for 8 to 16 hours, ball milled under controlled conditions, pelletized again and sintered in an oxygen atmosphere at 900 to 1000° C. for up to 72 hours. The polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y thus produced is in the form of elongated crystals having an average length of 2 to 10 μm and an average width of 1 to 2 μm, and embedded with spherical nanoparticles of yttrium deficient Y.sub.3Ba.sub.5Cu.sub.8O.sub.y having an average diameter of 5 to 20 nm. The spherical nanoparticles are present as agglomerates having flower-like morphology with an average particles size of 30 to 60 nm. The ball milled polycrystalline Y.sub.3Ba.sub.5Cu.sub.8O.sub.y prepared under controlled conditions shows significant enhancement of superconducting and flux pinning properties.

A method for the preparation of a composite article containing aerogel particles and ceramic fibers, as well as to a composite article obtained by this method, are described.