The present invention relates to a two-stage sintering method for preparing a porous biphasic calcium phosphate ceramic from calcium-containing biological waste, wherein hydroxyapatite prepared from calcium-containing waste is mixed with a foaming agent to prepare a bone graft material having medicinal use through two-stage sintering.

The invention concerns the area of ceramics an relates to a method for separating impurities from silicon carbide, said method being applicable to SiC powders from grinding sludges, and to temperature-treated and purified silicon carbide powder. The aim of the invention is to provide a method with which different impurities are substantially completely removed using a simple and economical process. This is achieved by a method in which pulverulent SiC waste products that have a mass percent of SiC of at least 50% and an average grain size d.sub.50 ranging from 0.5 to 1000 μm and have been subjected to a temperature treatment and cooled are mechanically treated and physically separated. The physically separated SiC powder is then divided into two fractions, one of which has a mass of impurities that is greater than the mass of impurities in the other fraction at least by a factor of 2.

The method is for use with a substrate having a plurality of parallel channels extending therethrough. In the method, the steps comprise: filling a selected plurality of the channels with a granular material; and consolidating the granular material through heat. The selected plurality of channels is selected to produce a wall that separates the substrate into: a first portion having a first plurality of the parallel channels extending therethrough; and a second portion having a second plurality of the parallel channels extending therethrough.

The present invention relates to a process for sintering a compacted powder of at least one oxide of a metal selected from an actinide and a lanthanide, this process comprising the following successive steps, carried out in a furnace and under an atmosphere comprising an inert gas, dihydrogen and water: (a) a temperature increase from an initial temperature T.sub.I up to a hold temperature T.sub.P, (b) maintaining the temperature at the hold temperature T.sub.P, and (c) a temperature decrease from the hold temperature T.sub.P down to a final temperature T.sub.F, in which the P(H.sub.2)/P(H.sub.2O) ratio is such that: 500<P(H.sub.2)/P(H.sub.2O)≦50 000, during step (a), from T.sub.I until a first intermediate temperature T.sub.i1 between 1000° C. and T.sub.P is reached, and P(H.sub.2)/P(H.sub.2O)≦500, at least during step (c), from a second intermediate temperature T.sub.i2 between T.sub.P and 1000° C., until T.sub.F is reached.

The present invention provides compositions and methods for converting hazardous waste glass into safe and usable material. In particular, the present invention provides compositions and methods for producing ceramic products from toxic-metal-containing waste glass, thereby safely encapsulating the metals and other hazardous components within the ceramic products.

The present invention relates to a metal matrix composite (MMC). The MMC includes a preform formed from a composition having ceramic particles and ceramic fibers and defining a plurality of voids. The metal matrix composite also includes a support element, such as a metal, disposed within the voids of the preform. The MMC has a wear surface defined by both the preform and the support element.

A sintering-free inorganic ceramic brick-plate and its preparation method are disclosed. The sintering-free inorganic ceramic brick-plate includes following components by mass parts: 25-40 parts of magnesium oxide; 20-35 parts of magnesium chloride; 20-30 parts of fumed silica; 10-20 parts straw powders; 0.1-0.3 parts of graphene powders with a particle size of 2000 meshes; and 0.2-0.4 parts of airgel powders with a particle size of 100 nm. Compared with the prior art, the present invention utilizes a variety of raw natural non-toxic natural mineral raw materials, namely, the graphene powders with the particle size of 2000 meshes and the airgel powders with the particle size of 100 nm for mixing, and then the mixed raw materials can be solidified at room temperature and form sheets, and then the surface of the sheets is processed through printing or spraying glaze, so as to achieve the effect of high-grade tiles and natural marble.

There is provided an apparatus and process for manufacturing a brick or paver with a high content of coal ash (ranging from 60% to 100% coal ash or fly ash) so that a waste product (coal ash, and more particularly Class F coal ash) from a coal-fired power plant is incorporated into a building product (high content fly ash brick or paver). Also provided is a variable firing tray to support the dried, high content coal ash bricks/pavers as the dried products are sent through a tunnel kiln, to improve circulation around the individual bricks/pavers and thereby result in reduced firing time in the kiln.

A method of making a proppant may include adding a dry ceramic precursor to a granulator, adding a slurry to the granulator, granulating the dry ceramic precursor and the slurry to form densified granules, and firing the densified granules to form a ceramic proppant. The dry ceramic precursor may include an alumina- or aluminosilicate-containing material, such as, for example, at least one of kaolin, ball clay, bauxitic kaolin, smectite clay, bauxite, gibbsite, boehmite, metakaolin, or diaspora. The slurry may include a recycled proppant material, such as, a fired recycled proppant material or a green recycled proppant material.

A carbon ceramic brake disc according to the present invention includes: a support body having cooling channels at the center portion; and friction layers directly attached to the top and the bottom of the support body without a bonding layer and having components different from the components of the support body, in which the support body is composed of a plurality of layers having components similar to the friction layers, gradually toward the friction layers from the cooling channels as the center. Accordingly, the support body can perform thermomechanical shock absorbing that is an original function and the friction layers and the support body can be prevented from separating while the carbon ceramic brake disc is manufactured.