A process for densification of a ceramic matrix composite comprises forming a reinforcing ceramic continuous fiber stack having a central zone bounded by an outer zone adjacent; locating first particles within the central zone; coating the first particles and the ceramic fibers with silicon carbide through chemical vapor infiltration; locating second particles within the outer zone; coating the second particles and the ceramic fibers with silicon carbide through chemical vapor infiltration; forming the stack into a predetermined three dimensional shape; and densifying the stack.

A method for welding together at least two parts of green material, referred to as green parts, by means of co-sintering, comprising the following steps:assembling the at least two green parts at a junction zone of said parts so as to form a green one-piece assembly,de-binding the green one-piece assembly, andsintering the one-piece assembly so as to obtain a dense one-piece assembly forming a final part, characterised in that the two green parts (10, 12) each have a composition of different powder, so as to produce a final part (1) having at least two parts with different grain sizes.

A novel composite diamond film comprising of a relatively thick layer of UNCD (Ultrananocrystalline Diamond) with a Young's modulus of less than 900 GPa and a relatively thin MCD (microcrystalline diamond) outermost layer with a Young's modulus of greater than 900 GPa, has been shown to exhibit superior delamination resistance under extreme shear stress. It is hypothesized that this improvement is due to a combination of stress relief by the composite film with a slightly softer UNCD layer, a disruption of the fracture mechanism through the composite layer(s), and the near ideal chemical and thermal expansion coefficient match between the two diamond layers. The combination of a thick but softer underlying UNCD layer with a thin but harder overlying MCD layer provides an excellent compromise between the low deposition cost and smoothness of UNCD with the extreme hardness and unparalleled chemical, electrochemical and immunological inertness of even a thin layer of MCD. The MCD layer's roughness is minimized and its adhesion maximized by the use of a thin layer of MCD and its deposition on the smooth surface of the chemically nearly identical underlying UNCD layer. The composite film can be applied to any application currently utilizing a diamond or a similar hard film, including cutting tools, abrasive surfaces, electrochemistry, biomedical applications such as human implants or thermally conductive films and the like, requiring superior durability, chemical resistance and/or immunological inertness.

A process for densification of a ceramic matrix composite comprises forming a reinforcing ceramic continuous fiber stack having a central zone bounded by an outer zone adjacent; locating first particles within the central zone; coating the first particles and the ceramic fibers with silicon carbide through chemical vapor infiltration; locating second particles within the outer zone; coating the second particles and the ceramic fibers with silicon carbide through chemical vapor infiltration; forming the stack into a predetermined three dimensional shape; and densifying the stack.

A multilayer ceramic capacitor includes a multilayer body in which a plurality of internal electrodes including Ni and a plurality of ceramic dielectric layers are alternately stacked, and external electrodes. The ceramic dielectric layer includes an inner dielectric layer located between internal electrodes, and an outer dielectric layer located outside in a stacking direction and including at least NiO. A difference between average grain sizes of dielectric grains of the outer dielectric layers and the inner dielectric layers is about 10% or less. A molar amount of NiO with respect to about 100 moles of Ti is larger by about 0.6 mole or more in the outer dielectric layer than in the inner dielectric layer.

The present invention relates to refractories with a composition gradient for lining the interior surface of combustion chambers. The invention envisages the use of refractories characterized by the presence of a number of layers with a different chemical composition to form a gradient along the cross section of the material. The presence of the composition gradient serves to combine the corrosion resistance of the surface layer, facing towards the inside of the combustion chamber, with the shock resistance of the bulk material.

A thermal conductive member includes: first and second surface layers including an insulating material A, and an intermediate layer including an insulating material B. The insulating material A includes a first boron nitride sintered body having an orientation degree of hexagonal boron nitride primary particles of 0.6 to 1.4, and a first heat curable resin composition impregnating in the first boron nitride sintered body. The insulating material B includes a second boron nitride sintered body having an orientation degree of hexagonal boron nitride primary particles of 0.01 to 0.05, and a second heat curable resin composition impregnating in the second boron nitride sintered body.

A composition may include granules in which zirconia particles are aggregated. The granules may have an average circularity of 0.81 or greater based on a projected image. The zirconia crystal system of the zirconia particles may be 20% or more monoclinic. An angle of repose of the composition, measured in accordance with JIS R9301-2-2, may be in a range of from 20 degrees to 35 degrees.

A composition includes granules in which zirconia particles are aggregated. The granules have an average circularity of 0.81 or greater based on a projected image.

The present invention relates to a polycrystalline diamond compact. A method for manufacturing a polycrystalline diamond compact includes: preparing primary sintering by mixing and assembling first diamond particles and metal binder particles; sintering the mixed and assembled particles; leaching the upper surface of the sintered polycrystalline diamond compact; preparing secondary sintering by mixing second diamond particles and the metal binder particles and assembling the mixed particles on the upper surface of the primarily sintered polycrystalline diamond compact; sintering the sintered polycrystalline diamond compact and the mixed particles of the upper part; and a grinding step of grinding the reassembled second diamond particles and metal binder particles so as to remove the same. The polycrystalline diamond compact minimizes the content of the residual metal binder in a surface layer and increases the content of the diamond particles with high thermal conductivity, thereby increasing the lifespan of the polycrystalline diamond compact.