A method for forming rod-shaped particles includes reducing a length of rods derived from a slurry made up of particles and a reactant, wherein the rods are in a stabilized state in which the reactant has been at least partially reacted with a coagulant, but the rods have not been sintered, and subsequently sintering the reduced length stabilized rods. The reducing the length of the stabilized rods includes subjecting the stabilized rods to mechanical vibration applied by a device, or feeding the stabilized rods through a device having a rotating cutting mechanism.

Various shaped abrasive particles are disclosed. Each shaped abrasive particle includes a body having at least one major surface and a side surface extending from the major surface.

A method for manufacturing a part from a first ceramic or from carbon, consolidated by a second ceramic, having a determined geometry, that involves carrying out the following sequence of steps: a) manufacturing a preform made from an organic polymer; b) impregnating the preform made from an organic polymer with a resin that is a precursor of the first ceramic or a resin that is a precursor of carbon; c) crosslinking and/or polymerising, then pyrolysing the resin that is a precursor of the first ceramic or the resin that is a precursor of carbon; to obtain a part made from a first ceramic or from carbon having the same geometry as the part to be manufactured; e) depositing the second ceramic on the part made from a first ceramic or from carbon by means of a chemical vapour deposition or CVD process or a chemical vapour infiltration or CVI process.

An armor component and manufacturing thereof which includes a ceramic hard material, where the hard material has a bulk density that is lower than 3.5 g/cm.sup.3 and includes grains of ceramic material having a Vickers hardness that is higher than 15 GPa, bonded by an bonding matrix, the bonding matrix representing between 20 and 80% by weight of the constituent hard material of the ceramic body, and including alumina, silicon nitride and TiC.sub.xN.sub.1-x crystalline phases, wherein x is included between 0 and 1.

A method for preparing a boron carbide material includes: providing raw materials of a boron material, a carbon material and a rare earth oxide, wherein an element molar ratio B:C of the boron material to the carbon material is in a range of 4:1 to 4:7, and the rare earth oxide is in an amount of 5 wt % or less based on a total weight of the raw materials, mixing and milling the raw materials to obtain a mixture, compressing the mixture into a tablet form by a tablet press, and sintering the compressed mixture by a laser, wherein the laser has a laser wavelength of 980 nm, a laser power in a range of 100 to 3000 W, and a laser irradiation time of 3 to 60 s.

A method for manufacturing a pillar-shaped honeycomb fired body including: measuring a firing shrinkage at an end surface of a first pillar-shaped honeycomb firing body at every predetermined angle for one round based on a portion that has been located at the center of a die when a green body passes through the die, obtaining a second pillar-shaped honeycomb formed body having a corrected end surface contour by modifying an annular mask used for extrusion molding based on a result of the measuring, and then obtaining a second pillar-shaped honeycomb fired body by performing drying and firing.

An assembly for densification under load along at least one direction of compression. The assembly includes: at least one volume to be densified having a powdery and/or porous composition and having variations in thickness along the direction of compression; and at least one counter-form of a powdery and/or porous composition, having at least one face facing at least one portion of the volume. The face and each of the portions are separated by at least one deformable interface layer.

The present invention relates to a kit of parts comprising a dental mill blank comprising a porous zirconia material and a colouring solution for colouring the porous zirconia material. The porous zirconia material comprises Zr oxide calculated as ZrO2: from 80 to 97 wt.-%, Al oxide calculated as Al2O3: from 0 to 0.15 wt.-%, Y oxide calculated as Y2O3: from 1 to 10 wt.-%, Bi oxide calculated as Bi2O3: from 0.01 to 0.2 wt.-%, the porous zirconia material not comprising Fe calculated as Fe2O3 in an amount of more than 0.01 wt.-%, wt.-% with respect to the weight of the porous zirconia material. The colouring solution comprises solvent(s), colouring agent(s) comprising metal ions selected from Tb, Er, Pr, Mn or combinations thereof, the solution not comprising Fe ions in an amount of more than 0.01 wt.-%, the solution not comprising Bi ions in an amount of more than 0.01 wt.-%, wt.-% with respect to the weight of the colouring solution. The invention also relates to a process of producing a dental restoration, the process comprising the steps: providing a dental mill blank comprising a porous zirconia material as described in any of the preceding claims, machining an article out of the porous zirconia material, the article having the shape of a dental restoration with an outer and inner surface, providing a colouring solution as described in any of the preceding claims, applying the colouring solution to at least portions of the surface of the article having the shape of a dental restoration.

An elongate shaped abrasive particle comprises an elongate shaped ceramic body having opposed first and second ends joined to each other by at least two longitudinal sidewalls. At least one of the at least two longitudinal sidewalls is concave along its length. At least one of the first and second ends is a fractured surface. Methods of making elongate shaped abrasive particles and abrasive articles including them are also disclosed.

Provided are a sintered ceramic and a ceramic sphere which are inhibited from suffering surface peeling due to fatigue resulting from repetitions of loading and can attain an improvement in dimensional accuracy when subjected to surface processing and which have excellent wear resistance and durability.