Abstract: An apparatus and a method for measurement of transparent cylindrical articles during their manufacture in high temperature furnaces having openings for viewing the articles as they pass through the furnace. The cylindrical articles may, for example, be optical fiber preforms which have at least two layers of vitreous material and from which optical fibers are made. Measurement is accomplished using a digital camera with a sensing and digital recording device and a lens, and a processor programmed with an algorithm which analyzes the images recorded by the sensing and digital recording device by eliminating noise, identifying and locating the outer edges of the transparent cylindrical article and calculating measurements of the article including the diameter and the axial center of the article.

Abstract: An arrangement (1) including at least one workpiece (2) for sintering, more particularly a dental workpiece, and having at least one support material (3), and including a sintering apparatus (4) for sintering the workpiece (2), wherein the sintering apparatus (4) has at least one gas inlet duct (5) for protective gas and at least one base surface (6), and the workpiece (2) lies on the base surface (6) on the support material (3) and protrudes at least partially beyond the support material (3), wherein the protective gas can be supplied to the workpiece (2) preferably exclusively through the support material (3).

Abstract: A process for producing a ringlike oxidic shaped body by mechanically compacting a pulverulent aggregate introduced into the fill chamber of a die, wherein the outer face of the resulting compact corresponds to that of a frustocone.

Abstract: A process for producing a ringlike oxidic shaped body by mechanically compacting a pulverulent aggregate introduced into the fill chamber of a die, wherein the outer face of the resulting compact corresponds to that of a frustocone.

Abstract: The invention relates to a method for production of an object with an at least partly silicon carbide structure from a blank of a carbon-containing material, wherein, in a first step, the object made from the carbon-containing material is produced essentially in the desired end form and/or end size, the object made from the carbon-containing material is then at least partly enveloped in a carbon-rich silicon dioxide granulate and then fired at least once in the envelope in a protective gas atmosphere such that the silicon dioxide granulate gives off gas containing silicon carbide which diffuses into the object and the carbon-containing material is completely or partly converted into silicon carbide.

Abstract: A method comprising building at least one three-dimensional model and a support structure using a layer-based additive technique, where the at least one three-dimensional model is at least partially encased in the support structure, and where the support structure functions as a shipping package for the at least one three-dimensional model.

Abstract: A customer transmits their 3D CAD file for a part to be total profile machined. Computer analysis of the transmitted CAD file produces CNC machining instructions, which are transmitted back to an address defined by the customer. The customer can then use the transmitted CNC machining instructions to total profile machine their own part using their own CNC mill at the location where the part is likely needed. The transmitted instructions include not only the tool paths for CNC machining of the total profile of the part, but also for additional features formed into the encircling portion of a material block from which the part is to be total profile machined. For instance, the CNC machining instructions transmitted back to the customer can define a registration recess and/or channels or undercuts for fluid support material on an A-side of a material block. After the A-side of the block is machined, the customer adds and solidifies fluid support material into the machined recess.

Abstract: Methods of forming aluminum oxynitride (AlON) materials include sintering green bodies comprising aluminum orthophosphate or another sacrificial material therein. Such green bodies may comprise aluminum, oxygen, and nitrogen in addition to the aluminum orthophosphate. For example, the green bodies may include a mixture of aluminum oxide, aluminum nitride, and aluminum orthophosphate or another sacrificial material. Additional methods of forming aluminum oxynitride (AlON) materials include sintering a green body including a sacrificial material therein, using the sacrificial material to form pores in the green body during sintering, and infiltrating the pores formed in the green body with a liquid infiltrant during sintering. Bodies are formed using such methods.

Abstract: Methods for producing substantially round, spherical and sintered particles from a slurry of a calcined, uncalcined or partially calcined raw material having an alumina content of more than 55% by weight, and a mullite growth promoter in an amount of from about 2 to about 10% dry weight of the total solids in the slurry. Methods for using such substantially round, spherical and sintered particles in hydraulic fracturing operations.

Abstract: An aluminum nitride sintered body having resistance to plasma gas and high thermal conduction and having excellent optical properties. The aluminum nitride sintered body of the present invention is characterized in that the proportion of positrons which are annihilated within a period of 180 ps (picoseconds) in the aluminum nitride crystal, as determined in the defect analysis using a positron annihilation method, is not less than 90%, and the sintered body preferably has a thermal conductivity of not less than 200 W/mK.

Abstract: A translucent ceramic includes a perovskite-type compound as a main component having a composition represented by the general formula (La1-x(Sr1-a-bBaaCab)x)((Al1-cGac)1-y(Ta1-dNbd)y)vOw (wherein 0<x?1, 0<y?0.6, 0.4?y/x?0.6, 0?a?1, 0?b?1, 0?c?1, 0?d?1, 0.9?v?1.1 and w is a positive number for keeping an electrical neutrality). The translucent ceramic has a high refractive index and a large Abbe number. Therefore, the translucent ceramic has an advantage in correction of aberration and is preferably used for lenses, which are disposed so as to hold a diaphragm therebetween, in a Gauss lens optical system such as an optical system for a single-lens reflex camera.

Abstract: A primary sintered body having a density of 95 % or more obtained by sintering a zirconia powder comprising an yttria main component as a stabilizer under ordinary pressure is set in a vessel of a semi-sealed state and subjected to HIP treatment (secondary sintering) at a temperature of from 1,600 to 1,900° C. under a pressure of 50 MPa or higher, and according to need, heated treated in an oxidizing atmosphere, thereby producing a polycrystalline sintered body of zirconia having high transparency of an in-line transmission of 50% or higher.

Abstract: Methods of forming a colored ceramic body or dental article are described that include: (a) forming a body from a ceramic-containing powder; (b) shaping the body into a desired shape; and (c) firing the shaped body in an atmosphere comprising at least one coloring agent. Methods of forming a fully dense ceramic body that lacks discoloration, are also described which include: (a) forming a body from a ceramic-containing powder; (b) shaping the body into a desired shape; (c) placing the shaped body in a firing atmosphere containing at least one impurity that promote discoloration of the ceramic body; (d) placing the ceramic body in proximity to an atmosphere powder; and (e) firing the shaped body in proximity to an atmosphere powder; wherein the atmosphere powder acts as at least one of a barrier and a getter for the at least one impurity.

Abstract: A highly heat-conductive Si-containing material containing a Si phase whose lattice constant at room temperature is controlled at a level of more than 0.54302 nm but 0.54311 nm or less. Firing is conducted using a kiln material containing no B compound. With this highly heat-conductive Si-containing material and the process for production thereof, a reduction in heat conductivity can be prevented and a high heat conductivity can be exhibited stably.

Abstract: A method of exfoliating a layered material to produce separated nano-scaled platelets having a thickness smaller than 100 nm. The method comprises: (a) providing a graphite intercalation compound comprising a layered graphite containing expandable species residing in an interlayer space of the layered graphite; (b) exposing the graphite intercalation compound to an exfoliation temperature lower than 650° C. for a duration of time sufficient to at least partially exfoliate the layered graphite without incurring a significant level of oxidation; and (c) subjecting the at least partially exfoliated graphite to a mechanical shearing treatment to produce separated platelets. The method can further include a step of dispersing the platelets in a polymer or monomer solution or suspension as a precursor step to nanocomposite fabrication.

Abstract: A translucent ceramic having a high light transmittance is provided. It contains a perovskite compound having a composition represented by a general formula: (Ba1-s-tSrsCat)(MxB1yB2z)vOw (where M contains at least one of Sn, Zr and Hf, B1 represents at least one of Mg, Zn, Y and In, B2 represents at least one of Ta and Nb, each of conditions of 0?s?0.99, 0.01?t?0.45, x+y+z=1, 0<x?0.9, 1.00?z/y?2.40, and 0.97?v?1.05 is satisfied, and w represents a positive number for maintaining electrical neutrality) as a primary component. This translucent ceramic can be used as, for example, an objective lens (2) of an optical pickup (9) to provide advantages. In another aspect some of M is replaced by Ti.

Abstract: A method of producing metal oxide nanoparticles in an exfoliated silicate framework by forming an aqueous exfoliated silicate suspension by mixing a layered clay into water until clear. To which is added an acidic hydrated metal species precursor solution, formed by dissolving one or more transitional metal salts, and a non-ionic surfactant. This solution is then aged to precipitate a product precursor before the product precursor is separated and washed. The product precursor is calcined to form metal oxide nanoparticles in an exfoliated silicate framework.

Abstract: A ceramic sheet has a burr height on the periphery of the sheet of ±100 ?m or less and/or a dimple height on the sheet surface of 100 ?m or less, as determined by irradiating the sheet with a laser beam to measure reflected light, and three-dimensionally analyzing the reflected light with a laser optical three-dimensional profiling instrument. This sheet is highly resistant to stacking-induced loads and thermal stresses. Further, when the ceramic sheet includes a zirconia ceramic partially stabilized with 2.8 to 4.5% by mole of yttria and containing 0.1 to 2% by mass of at least one dispersed reinforcing oxide, in which the grain size of the surface of the sheet has an average of 0.1 to 0.4 ?m, a maximum of 0.4 to 0.8 ?m, and a coefficient of variation of 30% or less, which grain size is determined by scanning electron microscopic observation, the ceramic sheet has satisfactory strength at room temperature and at high temperatures and satisfactory durability of strength at high temperatures.

Abstract: The method for manufacturing a sintered piece comprises preparing a molded piece of a composite including calcium phosphate compound such as hydroxyapatite, and baking the molded piece in an oxygen atmosphere to obtain the sintered piece. The oxygen concentration of the oxygen atmosphere is controlled to be not less than 25 vol %, and the relative humidity of the oxygen atmosphere is controlled to be below 30% RH. The baking is performed for 30 minutes to 8 hours at a temperature not less than 1000° C. and below a temperature at which thermal decomposition of the calcium phosphate occurs.

Abstract: The invention relates to polymer ceramic composite materials with a virtually zero shrinkage compared to the original model after concluding partial pyrolysis and with a comparable thermal expansion behavior (preferably in an application range of 400° C. or less) to metal construction materials, in particular gray cast iron or steel, which are obtainable by methods described below; corresponding composite constructions and molded parts; and methods for producing and using these materials, composite constructions and molded parts. The polymer ceramic composite materials can for instance be used instead of or in contact with steel or gray cast iron temperature-proof molded parts, predominantly in mechanical engineering, without postmachining after the creative forming.

Abstract: A new method is disclosed for producing thin plates by sintering a thin gel plate (e.g., silica) made using a sol-gel process, which substantially eliminates warpage of the plate during the sintering step. Sintering a sol-gel based silica plate to a dense glass typically causes significant shrinkage, and this can cause the plate to curl, especially around its edges. This phenomenon is referred to as warpage. In the method of the invention, the sintering step is performed while the gel plate is mounted on a support surface, separated by a thin layer of refractory powder. At the high sintering temperature, the powder partially fuses and sticks to both the gel plate and the support surface, which prevents non-uniform stresses in the gel plate from warping the plate.

Abstract: A method for forming a sheet material suitable for use in manufacturing gliding board bases includes placing a first group of materials including plastic particles on a continuously moving surface in a first pattern, and placing a second group of materials including plastic particles on the continuously moving surface in a second pattern. Heat and pressure are applied to sinter the plastic particles together to form the sheet material having a first area with a first set of characteristics formed mainly of particles from the first group adjacent a second area with a second set of characteristics different from the first set of characteristics formed mainly from particles from the second group. The first and second sets of characteristics may include only one characteristic, such as color, hardness, wear-resistance, etc., or a plurality of different characteristics.

Abstract: The present invention provides a laminated body, comprising: a first sheet layer comprising an aggregate of a first powder, at least a part of the first powder being in a sintered state; a second sheet layer disposed so as to make contact with the first sheet layer and comprising an aggregate of a second powder, the second powder being in a non-sintered state; and the first powder and the second powder being solidified to each other by allowing a part of the first sheet layer material to diffuse or to flow into the second sheet layer.

Abstract: Flexible setter powder deposition sheets containing setter powders were developed for sintering of ceramic articles including tapes by an economical, fast and simple method. The sheets provide for deposition of a thin and uniform layer of setter powders on a green ceramic article after burnout of a binder in the sheet. Because of high strength and low burnout temperature, hydroxypropyl methylcellulose binder is preferred for production of these sheets. Tape cast sheets with low solids loading can be obtained by optimizing the wetting behavior of aqueous slurries on tape carrier. Setter, powder deposition sheets are of particular benefit in processing of thin ceramic tapes, particularly for processing of piezoelectric ceramic tapes. Tapes can be processed in a sandwich formed by layering setter powder deposition sheets between tapes and cover plates employed to maintain tape flatness and to reduce evaporation of volatile components of the ceramic.

Abstract: A method and crucible for annealing SiC at high temperatures. The crucible s a vessel having a peripheral wall, at least two compartments separated by an inner wall within the peripheral wall and a lid which separates the compartments from the crucible surroundings while providing a passageway between the compartments. The peripheral wall, inner wall and lid are composed of materials capable of withstanding annealing temperatures. The process disposes an SiC wafer in one of the compartments and SiC powder disposed in another of the compartments. The SiC powder is present to hinder SiC wafer decomposition during annealing of the SiC wafer. The crucible is then heated to a temperature sufficient anneal the SiC wafer, preferably after evacuating air and flowing an inert gas in and around the crucible.

Abstract: A method of manufacturing a ceramic arc chamber (420) comprising providing a sintering tray (412) including a plurality of bores (422). The bores (422) having a first diameter upper section (424) and a second narrower diameter lower section (426). Positioning a plurality of ceramic end caps (212) having a main body portion (216), and a leg portion (219) in the bores (422) such that the leg portion (219) passes downwardly through the narrower diameter lower section (426) and the main body portion (216) is retained within the upper section (424). Moreover, the second diameter lower section (426) acts as a shoulder supporting the end cap (210). Next, a ceramic arc tube (214) is positioned within the first diameter upper section (424) and mated with the ceramic end cap (212). A second end cap (210) is mated to a second upper open end of the ceramic arc tube (214) to form an arc tube preform (420). The arc tube preforms (420) are then sintered to join the components via controlled shrinkage.

Abstract: A method for producing a dental prosthesis to be fitted to a fitting member including the steps of: determining the three-dimensional contours of the fitting member; producing a three-dimensional form of the dental prosthesis; producing a working stump and/or a working pack; placing the working stump in the form and/or packing the working pack around the outside of the form to completely cover the form; sintering the form with the working stump and/or the working pack; and separating the working stump and/or the working pack from the dental prosthesis after sintering. The working stump and working pack are produced such that they are enlarged by a predetermined enlargement factor.

Abstract: A sintered ceramic material for high speed machining of heat resistant alloys is provided comprising SiAlON grains and 0.2-20 v/o intergranular phase. At least 80 v/o of said SiAlON phase is beta SiAlON having a z-value greater than 1.0, but less than 1.5. The ceramic material has a Vickers Hardness HV1 of more than 1530 and it is produced by gas pressure sintering.

Abstract: A sialon composite and fabrication method thereof in which the phase of a surface layer thereof is modified differently from that of the bulk. The surface layer is modified to .alpha.-sialon or .alpha.-.beta. sialon composite but the bulk is .beta.-sialon. Also, the surface layer is modified to .beta.-sialon or .alpha.-.beta. sialon composite but the bulk is .alpha.-sialon.

Abstract: A method for producing a long ceramic body, including the steps of pre-firing a non-fired long ceramic body at a first temperature for a sufficient time to achieve a shrinkage ratio in the body of 5% to 95%, thereby forming a pre-fired ceramic body, hanging the pre-fired ceramic body in a substantially vertical direction inside a sheath while maintaining a spacing between the pre-fired ceramic body and the sheath, applying a downward load to the pre-fired ceramic body at a position proximate the bottom end thereof, and firing the pre-fired body at a second temperature for a sufficient time to sinter the pre-fired ceramic body.

Abstract: A method for sintering tube pre-forms in an furnace for obtaining ceramic tubes which are extremely straight is provided, in which, during sintering, the tube preforms are placed inside supporting tubes in ceramic material, the support tubes 1 containing the tube preforms being arranged parallel to each other forming stacks 7 of layers 3 supported by support plates 4 in a refractory material, the inside surface of the support tubes being out-of-true by less than 0.1 mm over a length of 90 mm.

Abstract: A silicon nitride reaction-sintered body having a high mechanical strength without surface working can be produced by (1) forming a silicon powder mixture of at least two types of silicon powders having substantially independent particle size distribution ranges into a green body, the silicon powder mixture having an average particle size ranging from 5 .mu.m to 300 .mu.m; (2) heating the green body in a nitrogen-containing atmosphere for nitrogenation; and (3) sintering the nitrogenated green body at a temperature of 1900.degree. C. or higher.