Abstract: Pigment suspensions of inorganic pigments are prepare compacting and grinding the unground pigments on a roller compactor, followed by processing of the compacted pigment in a wet grinding mill with addition of water. The process as described improves the particle size distribution of the pigment.

Abstract: An abrasive compact comprising 40 to 90 volume percent of cubic boron nitride (CBN) crystals bonded by 60 to 10 volume percent of a bonding matrix comprised mainly of an intimate mixture of silicon nitride and metallic diboride MB.sub.2 where M represents metal atoms chosen from the group of titanium, zirconium and hafnium atoms. The compact may be produced by a method which comprises intimately mixing particulate CBN crystals with a bonding agent in the proportion 95 to 60 volume percent of CBN and 5 to 40 volume percent of bonding agent, the bonding agent containing the metal atoms in the atomic proportions Si.sub.30 M.sub.70 to Si.sub.85 M.sub.15, subjecting the mixture of CBN crystals and bonding agent to temperatures in the range 900.degree. to 1800.degree. C. and pressures in the range 5 to 70 Kilobars, and maintaining the temperature and pressure conditions for a period of at least about 30 seconds, sufficient to cause most of bonding agent to form the bonding matrix.

Abstract: A vitreous bonded abrasive article such as a grinding wheel is provided comprising high density sol-gel alumina-based abrasive grains comprised of alpha alumina and a vitreous bond which binds together the abrasive grains. The grinding wheel of the invention exhibits enhanced G-ratio grinding performance over comparable wheels containing sol-gel alumina-based abrasive grain having a density less than 3.85 grams per cubic centimeter.

Abstract: A one-piece abrasive sheet and method of manufacture. The abrasive pad has a planar sheet portion with a plurality abrasive protrusion extending therefrom. The protrusions are intimately molded with the planar sheet portion to form a one-piece sheet. Thermoplastic and abrasive grit mixture may be used to form the sheet. The resulting pad has improved durability.Also disclosed is an improved circumferentially outer lip structure with a ramp surface for improving performance of the pad over irregular surfaces or surfaces with edges or steps or the like.

Abstract: Alkyl polyglycoside surfactants are effective dispersing agents for TiO.sub.2 in aqueous dispersions.

Abstract: The invention relates to the manufacture of manganese dioxide by a chemical process. The resulting manganese dioxide product takes the form of particles characterized by filament-like protrusions jutting out from its surface. The manganese dioxide particles having such surface features can be manufactured by reacting manganese sulfate with sodium peroxodisulfate in an aqueous solution. The process can be controlled to yield high density manganese dioxide. The manganese dioxide formed in the process can be deposited directly onto the surface of electrolytic manganese dioxide (EMD). The manganese dioxide product the is particularly suitable for use as a cathode active material in electrochemical cells.

Abstract: A novel platey alumina with essentially no aggregates, fines or fragments has been obtained. This product proves very advantageous in lapping substrate wafers for microelectronic applications. A process for making such products is also described.

Abstract: A cutting body is formed of compacted powder and has a lower side provided with a recess and a spaced protrusion. The body can be used as a cutting insert, or two identical such bodies can be sintered together to form an invertible cutting insert. Voids can be formed within the insert to contain sensors or conduct cooling fluid.

Abstract: The present invention is directed to rotary drill bits and blanks which retain polycrystalline diamond or CBN compacts, but which do not suffer from disadvantages attendant by prior drill designs. The inventive rotary drill bit has a slot within the head thereof which slot has brazed therein with a brazing alloy preferably having a liquidus greater than 700.degree. C. an unsupported thermally-stable polycrystalline diamond or CBN compact. The drill bit is made in another aspect of the invention by forming a slot in the head of the rotary drill and then brazing an unsupported thermally-stable polycrystalline diamond or CBN compact therein with a brazing alloy preferably having a liquidus greater than 7000.degree. C. For present purposes, polycrystalline diamond and CBN compacts are termed "thermally stable" by being able to withstand a temperature of 1200.degree. C. in a vacuum without any significant structural degradation of the compact occurring.

Abstract: An abrasive composition and dental articles made from same, the composition including abrasive particles dispersed throughout and entrapped within a polyurea or polyurethane urea matrix which contains soft and hard segments wherein the matrix is made from the polymerization reaction of a polyfunctional amine and a polyfunctional isocyanate. The abrasive dental articles include prophylactic cups and polishing wheels, points and discs.

Abstract: A light-modifying composition comprising a color pigment component and a pigment spacer component characterized by being a transducing material having the ability to absorb light and reflect at least part of the light absorbed, thereby modifying the light in the coating resulting from the application of the composition. Such pigment spacing component includes any material having the ability to partially absorb light. Preferred are neutral grey pigments in the form of grey powders having a minimal color producing effect. The pigments can be in the form of ground grey powders such as powders taken from granite, feldspar, quartz or limestone or in the form of spherical metallic particles such as metallic zinc.

Abstract: Bonded abrasive compositions, articles incorporating same, and methods of making the compositions and articles are presented, the compositions comprising abrasive particles dispersed throughout and adhered within an elastomeric polyurea matrix. The polyurea matrix is formed from the polymerization reaction product of a polyfunctional amine and an isocyanate. The compositions exhibit excellent smear- and wear-resistance, and may be attached to a variety of backings. One preferred backing is integrally molded to the bonded abrasive composition.

Abstract: A sintered polycrystalline compact of cubic boron nitride is made by forming a mixture of about 45 to 65 percent by weight cubic boron nitride (cBN), from about 30 to 45 percent by weight hexagonal boron nitride (hBN), and from about 2 to 7 percent by weight an aluminum containing material, preferably aluminum nitride, and cobalt aluminide having a melting temperature lower than the melting temperature of cobalt phase. The mixture of cBN crystals, hBN and adjuvant materials is compacted into preforms and subjected to heat treatment in a non-oxidizing atmosphere. The preforms are placed onto a cemented tungsten carbide substrate containing cobalt and subjected to elevated pressure and temperature conditions at which the boron nitride is thermodynamically stable. The elevated pressure and temperature conditions are maintained for a time sufficient to permit the infiltration of a cobalt phase into the cBN matrix and sinter the compact.

Abstract: Coatable mixtures including erodable filler agglomerates, and abrasive articles into which they may be incorporated are presented, the agglomerates comprising a plurality of individual grains of water insoluble filler agglomerated by an agglomerating agent which includes water soluble filler and a binder. A preferred water soluble filler is Al.sub.2 (SO.sub.4).sub.3.14-18H.sub.2 O, a preferred water insoluble filler is Na.sub.3 AlF.sub.6 (cryolite), while a preferred binder is a phenolic resin. Methods of making coatable mixtures including erodable filler agglomerates are also presented.

Abstract: Synthetic abrasive stones and method for making same. A mixture of glass and 10-20% by weight foaming agent is provided. The mixture is heated to a temperature of from 788.degree. to 899.degree. C., and is then cooled to room temperature.

Abstract: This invention relates to a composition comprising: water; particulate abrasive dispersed in said water, said abrasive having a Knoop scale hardness of at least about 1000 and an average particle size of from about 1 micron up to a U.S. Sieve Series Number of about 50; and an effective amount of at least one thickener to maintain a stable dispersion of said abrasive in said water. The inventive composition can contain one or more surfactants and/or one or more chelating agents. In one embodiment the invention provides for a water-based polish that can be used on any nonporous surface (e.g., glass, plastic, metal, painted surfaces, waxed surfaces, marble, ceramic, soft-precious and semi-precious stones, semi-conductor materials, metallurgical and geological specimens, Formica, etc.).

Abstract: An abrasive composition for use in polishing or planarizing the surface of a work piece is provided comprising about 30 to 50 percent of cerium oxide; about 8 to about 20 percent of fumed silica and about 15 to about 45 percent of precipitated silica. Methods using the composition to polish or planarize the surfaces of work pieces, as well as products produced by such methods, are also provided.

Abstract: An abrasive system and a processing procedure is provided which permits the direct installation of a thick abrasive blade tip cap onto a cast single crystal turbine rotor blade during a single heating schedule requiring only one furnace operation. The composition of the abrasive blade tip cap advantageously utilizes the high temperature performance capabilities of the single crystal alloy without significantly affecting its mechanical properties as a consequence of the processing necessary to permanently bond the abrasive blade tip cap to the rotor blade. A semi-rigid blade tip cap preform is first formed and positioned on the tip of the rotor blade. The preform and rotor blade are then heated in a vacuum furnace according to a temperature schedule entailing heating rates, holding temperatures and durations which are sufficient to bond and consolidate the preform. The rotor blade is then rapidly cooled in the vacuum furnace to retain the single crystal structure of the rotor blade.

Abstract: The invention relates to polycrystalline, sintered abrasive granules based on .alpha.-Al.sub.2 O.sub.3 with a density of >98% of the theoretical density of corundum, a Vickers hardness of 21 GPa and greater and a crystallite size of 0.05 to 1.3 micron, as well as abrasives made from these abrasive granules and the use of these abrasive granules for the production of ceramic, refractory products.The polycrystalline, sintered abrasive granules based on .alpha.-Al.sub.2 O.sub.3 are produced by .alpha.-Al.sub.2 O.sub.3 crystal nuclei being added to a boehmite dispersion, the mixture of the boehmite dispersion and the crystal nuclei being acidified and gelled and the gel being dried, crushed, and sintered. In doing so, 0.5 to 35% by weight of .alpha.-Al.sub.2 O.sub.3 crystal nuclei, relative to the sintered abrasive granules, is added and the mixture of the boehmite dispersion and of the crystal nuclei is refluxed, while the pH of the mixture is kept in a range of 2.5 to 3.5 by adding acid.

Abstract: A granular abrasive material is produced from a dispersion consisting of raw materials containing alumina, compounds containing silica and other additives. The dispersion is ground to a sinterable slip with a grain size of less than 1 micrometer. The slip is dried and may be pressed before being subjected to a multi-stage heating process to produce sintered corundum crystals.