Abstract: Optical components can be pressed with such a precision that grinding and polishing of the formed components is not necessary, from glasses containing 45-55 wt. % P.sub.2 O.sub.5, 3.5-9 wt. % Al.sub.2 O.sub.3, 5-20 wt. % K.sub.2 O, 0-3 wt. % Li.sub.2 O, 8-15% BaO, 4.5-9 wt. % ZnO, 0-6 wt. % MgO, 0-18 wt. % PbO, 0-1 wt. % SiO.sub.2, 0-3 wt. % B.sub.2 O.sub.3, 0-2 wt. % TiO.sub.2.

Abstract: Carbonaceous bonded refractory shapes in which the predominant refractory aggregate is andalusite, being characterized by the absence of substantial shrinkage after coking at 2000.degree. F.

Abstract: This invention is directed to the production of transparent photochromic glasses containing silver halide crystals sensitized with copper having base compositions within the alkali metal aluminoborosilicate system wherein at least 0.025% As.sub.2 O.sub.3 and/or Sb.sub.2 O.sub.3 is present in the composition to insure that more than 50% of the copper is present in the Cu.sup.+ state. Where an oxidizing agent is added to the composition, the amount of As.sub.2 O.sub.3 and/or Sb.sub.2 O.sub.3 will be increased to reduce that agent plus insure that more than 50% of the copper is present in the Cu.sup.+ state.

Abstract: An optical and ophthalmic glass having an index of refraction of .gtoreq.1.69, an Abbe number of .gtoreq.37, and a density of .ltoreq.3.30 g/cm.sup.3, consists essentially of (in % by weight):______________________________________ SiO.sub.2 18-36 B.sub.2 O.sub.3 3-18 GeO.sub.2 0-8 Al.sub.2 O.sub.3 0-6, wherein SiO.sub.2 + B.sub.2 O.sub.3 + Al.sub.2 O.sub.3 + GeO.sub.2 25-39 P.sub.2 O.sub.5 0-14, wherein SiO.sub.2 + B.sub.2 O.sub.3 + Al.sub.2 O.sub.3 + GeO.sub.2 + P.sub.2 O.sub.5 = 30-44 Li.sub.2 O 0-12 Na.sub.2 O 0-14 K.sub.2 O 0-18 Li.sub.2 O + Na.sub.2 O + K.sub.2 O = 2-18 MgO 0-15 CaO 7-25 MgO + CaO 15-32 SrO 0-13 BaO 0-17 ZnO 0-15 PbO 0-10 SrO + BaO + ZnO + PbO 0-20 TiO.sub.2 3-14 Nb.sub.2 O.sub.5 0-13 WO.sub.3 0-10 TiO.sub.2 + Nb.sub.2 O.sub.5 + WO.sub.3 = 10-21 ZrO.sub.2 0-15, La.sub.2 O.sub.3 0-20 Y.sub.2 O.sub.3 0-16 Gd.sub.2 O.sub.3 0-16 Yb.sub.2 O.sub.3 0-10 La.sub.2 O.sub.3 + Y.sub.2 O.sub.3 + Gd.sub.2 O.sub.3 + Yb.sub.2 O.sub.3 = 0-20 Ta.sub.2 O.sub.5 0-13 HfO.sub.2 0-5 SnO.sub.2 0-6.

Abstract: A panel glass of a color cathode ray tube exhibiting a high absorption of X-radiation and an excellent resistance to electron and/or X-ray browning, which is modified by 0.1-5.0 wt % Nd.sub.2 0.sub.3 to provide substantially higher relative light transmission in the green and in the red wavelengths of the visible spectrum and a greater selective light absorption in the yellow region of the spectrum, and which is further modified by 0.0005-0.05 wt % Cr.sub.2 O.sub.3 and 0-2 wt % Pr.sub.6 O.sub.11 to control the chromaticity value of the glass to be nearly equal to that of the light emitted from tricolor phosphor P22 and to suppress the dichroism of the glass for different ambient lights. Ingredients of the glass are as follows: 50-75% SiO.sub.2, 0-5% Al.sub.2 O.sub.3, 0-4% CaO, 0-3% MgO, 0-13% SrO, 0-16% BaO, 0-3% PbO, O-3% ZnO, 0-4% ZrO.sub.2, the sum of SrO+BaO+PbO+ZnO+ZrO.sub.2 being 5-25%, 0-4% Li.sub.2 O, 3-15% Na.sub.2 O, 2-15% K.sub.2 O, the sum of Na.sub.2 O+K.sub.2 O being 5-20%, O-2%, TiO.sub.

Abstract: The instant invention is directed toward the production of an alkali metal-free glass-ceramic body wherein the predominant, and preferably sole, crystal phase is a calcium fluorophlogopite. The body is strong, chemically durable, exhibits excellent electrical properties, and has a base composition consisting essentially, expressed in weight percent on the oxide basis, of aboutCaO: 5-20MgO: 15-25Al.sub.2 O.sub.3 : 5-20SiO.sub.2 : 35-60F: 5-15which is nucleated with 0.5-3.5% BaO+SrO, consisting of 0-3.5% BaO and 0-2.5% SrO, or, if BaO and/or SrO are absent, with 8-15% TiO.sub.2. The preferred products exhibit a white, translucent appearance and excellent resistance to staining.

Abstract: The invention relates to a sintered compact for use in an ultrahard tool having high resistance to heat and wear, outstanding thermal conductivity and thermal shock resistance property at elevated temperature, and suitable for high-speed cutting, and to a method for producing the same. A powder mixture comprising 20-80 volume % high pressure form boron nitride powder, the residual part consisting of Al.sub.2 O.sub.3 powder or a compound ceramic powder principally comprising Al.sub.2 O.sub.3 powder and also containing carbides, nitrides of IVb, Vb, VIb metals of the periodic table, mutual solid solution thereof or admixture thereof, is sintered as it stands or after pressing under a high pressure and a high temperature so that Al.sub.2 O.sub.3 of the compound ceramic constitutes a continuous phase in the structure of the sintered compact, and the half width of (116) in the X-ray diffraction of CuK.alpha. ray of Al.sub.2 O.sub.

Abstract: A basic brick composition containing spinel clinker and magnesia clinker wherein pulverized iron oxide by additional weight mixing ratio is mixed or special magnesia clinker is substituted for magnesia clinker instead of addition of iron oxide.

Abstract: Boron rich cubic boron nitride suitable for use in electroplating processes (e.g. nickel plating) has been made by an acid leaching process. Boron rich aggregated cubic boron nitride grinding grits are leached in a mixture of nitric and sulfuric acids, the following conditions being typical;(a) volume ratio of 67% nitric acid to 98% sulfuric acid of 10:20;(b) temperature of 250.degree. C; and(c) for a time of 1 hour.The process removes sufficient free surface boron to reduce the conductivity at the surface, resulting in an abrasive which does not overplate.FIG. 1 is a photomicrograph of a typical plated surface containing the improved CBN grinding grit of this invention, and FIG. 3 is an X-ray diffraction pattern characteristic of this new product.

Abstract: Hot pressing of fluoride glasses is provided. These glasses are synthesized from ZrF.sub.4 -BaF.sub.2 and HfF.sub.4 -BaF.sub.2 systems. Hot pressing rough blanks in a closed die made of hard, polished, optically-figured material, such as cobalt-bonded tungsten carbide, is done by pressing the glasses at a temperature between that of the softening point of the glass and its crystallization temperature and at a pressure sufficient to cause flow of the glass at the pressing temperature. As a consequence, mechanical polishing steps on all glass surfaces is eliminated, thereby minimizing surface contamination.

Abstract: An anti-wear sintered alloy comprising chrome 2.5-7.5 weight %, manganese 0.10-3.0 weight %, phosphorus 0.2-0.8 weight %, copper 1.0-5.0 weight %, silicon 0.5-2.0 weight %, molybdenum 0-3 weight %, and carbon 1.5-3.5 weight %, the balance being Fe and less than 2% impurities, and a process of manufacturing therefore.

Abstract: An inorganic black pigment is made by calcining raw materials such as manganese dioxide, manganese carbonate, strontium carbonate or calcium carbonate. The product is a perovskite structure made up of (a) 25-84 mol % of a manganese oxide and (b) 75-16 mol % SrO and/or CaO plus residual carbonates and mineralizers. The thus-produced black pigment is particularly advantageous in that it contains no heavy metals or highly toxic material and that it has very low oil absorption and high tinting strength.

Abstract: A silver halide glass is formed from silver iodide, silver fluoride and aluminum fluoride.

Abstract: A composition is disclosed for use in forming ceramic articles having improved color, density, bonding strength and mechanical strength. Ceramic particles are slurried with a composition that tends to minimize inclusion of bubbles of gas, e.g., air, and also minimize interstitial voids between the ceramic particles. In a preferred mode, the ceramic particles are slurred with an aqueous solution of sodium hydroxide having, for example, a sodium hydroxide concentration, by weight, in the order of about 0.02% to about 0.03%. The aqueous solution of the sodium hydroxide is added to a powered ceramic until a workable past or slurry is obtained. Articles are formed using the paste or slurry or the paste or slurry is built-up on a support and the ceramic is then fired to fuse the particles.

Abstract: A porcelain composition comprising Pb(Fe.sub.2/3 W.sub.1/3)O.sub.3, PbTiO.sub.3 and Pb(Yb.sub.1/2 Nb.sub.1/2)O.sub.3 preferably within the range as defined by closed area of A-B-C-D-A in the accompanying triangular diagram can give a sintered product by sintering at a temperature as low as 1000.degree. C. or lower. The resulting sintered product has a high relative dielectric constant and a small dielectric loss tangent.

Abstract: The instant invention is concerned with the preparation of glass-ceramic coatings capable of being fired repeatedly to temperatures in excess of 950.degree. C. without thermal deformation and being particularly suitable for application to low carbon and titanium-stabilized stainless steels. The coatings are substantially free from alkali metal oxides and consist essentially, expressed in terms of weight percent on the oxide basis, of:______________________________________ BaO 10-60 B.sub.2 O.sub.3 5-30 SiO.sub.2 25-40 Al.sub.2 O.sub.3 0-15 CaO 0-15 MgO 10-35 ZnO 0-16 Al.sub.2 O.sub.

Abstract: An infrared ray-transmitting glass composition for optical fibers consisting essentially of 28 mol % to 38 mol % of BaF.sub.2, 2 mol % to 7 mol % of GdF.sub.3 and 58 mol % to 69 mol % of ZrF.sub.4, and optical fibers comprising said glass composition.

Abstract: The invention provides a novel highly refractory sintered body based on a tal diboride such as TiB.sub.2 or Mo.sub.2 B.sub.5 and W.sub.2 B.sub.5 containing a binder ingredient. The high-temperature performance of the sintered body is further improved by including an auxiliary additive ingredient selected from several carbides, nitrides, silicides and oxides such as WC, TiC, TaN, TiN, MoSi.sub.2, TiO.sub.2, Al.sub.2 O.sub.3, B.sub.2 O.sub.3 and the like in a limited amount.

Abstract: This invention is directed to the preparation of transparent glasses displaying a light gray-brown tint that consist essentially, in weight percent on the oxide basis, ofSiO.sub.2 --80-82B.sub.2 O.sub.3 --11.25-12Na.sub.2 O--5.25-6Al.sub.2 O.sub.3 --1.9-2.1MnO.sub.2 --0.05-0.5NiO--0.01-0.07Cr.sub.2 O.sub.3 --0.005-0.

Abstract: Metal/ceramic abradable seals of the type used in jet aircraft are improved by using a substrate which is able to deform during cooling from the brazing temperature and then rendering the substrate rigid after the cool down.