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 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.

Phosphors include a CaAlSiN.sub.3 family crystal phase, wherein the CaAlSiN.sub.3 family crystal phase comprises at least one element selected from the group consisting of Mn, Ce, Pr, Nd, Sm, Eu, Tb, Dy, Ho, Er, Tm, and Yb.

A pore-free ceramic is provided that has a high modulus of elasticity and a low coefficient of thermal expansion. A process for producing a corresponding ceramic is also provided. The pore free ceramic is a dimensionally stable substrate material in applications subjected to temperature gradients including semiconductor manufacture.

Provided is a ceramic composite material and a wavelength converter. The ceramic composite material includes: an alumina matrix, a fluorescent powder uniformly distributed in the alumina matrix, and scattering centers uniformly distributed in the alumina matrix, wherein the alumina matrix is an alumina ceramics, the scattering centers are alumina particles, the alumina particles each have a particle diameter of 1 μm to 10 μm, and the fluorescent powder has a particle diameter of 13 μm to 20 μm.

The novel process enables designing of raw materials and processing parameters, enabling synergistic and simultaneous chemical reactions among the various reactants of the design mix of chemical precursor of brine sludge which includes barium sulphate, magnesium hydroxide, calcium carbonate, sodium chloride, silica, aluminum containing compounds necessary for developing highly efficient shielding phases leading to homogenous matrix of shielding materials.

An embodiment of a PCD insert comprises an embodiment of a PCD element joined to a cemented carbide substrate at an interface. The PCD element has internal diamond surfaces defining interstices between them. The PCD element comprises a masked or passivated region and an unmasked or unpassivated region, the unmasked or unpassivated region defining a boundary with the substrate, the boundary being the interface. At least some of the internal diamond surfaces of the masked or passivated region contact a mask or passivation medium, and some or all of the interstices of the masked or passivated region and of the unmasked or unpassivated region are at least partially filled with an infiltrant material.

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 particulate filter and method of manufacture. The particulate filter comprises a ceramic honeycomb body comprising a plurality of intersecting walls that define a plurality of channels extending longitudinally though the ceramic honeycomb body. The intersecting walls comprise a porous ceramic material having a microstructure that comprises an interconnected network of porous spheroidal ceramic beads. The microstructure has a total porosity defined as the sum of an open intrabead porosity of the beads and an interbead porosity defined by interstices between the beads in the interconnected network. The microstructure has a bimodal pore size distribution in which an intrabead median pore size of the intrabead porosity is from 1.5 μm to 4 μm and an interbead median pore size of the interbead porosity is from 6 μm to 20 μm.

A refractory object may include a zircon body that is intentionally doped with a dopant including an alkaline earth element and aluminum. The refractory object can have an improved creep deformation rate. In an embodiment, the refractory object can have a creep deformation rate of not greater than about 1.8 E-5 h.sup.−1 at a temperature of 1350° C. and a stress of 2 MPa. In another embodiment, the zircon body may include an amorphous phase including an alkaline earth metal element.