Abstract: A method for forming integral extensions on the end of directionally oriented, superalloy articles, such as airfoil blading members or other components used in gas turbine or other turbine engines. An extension is formed directly on an article by dipping a portion or end of the article into a molten bath of a compatible alloy, followed by withdrawal of the end under controlled conditions sufficient to cause an integral extension to solidify on the article. A ceramic mold is utilized over the dipped end of the article with a mold cavity that generally defines the shape of the extension to be formed. The mold may be formed in situ, or preformed and attached to the subject article. Extensions formed by the method of this invention have a microstructure that is continuous and compatible with that of the article. Such microstructures may include epitaxial growth of the extension from the microstructure of the article.

Abstract: Nb-base alloys that include Ti, Hf, Cr, Al and Si as alloy constituents have a microstructure that includes a metallic solid solution phase and a mixture of intermetallic silicide phases. The metal silicide phases include an M.sub.3 Si silicide, where M comprises Nb, Ti or Hf, and an M.sub.5 (Si, Al).sub.3 silicide, where M comprises Nb, Ti or Hf. These alloys have mechanical properties such as low temperature fracture toughness, high temperature fracture strength, high temperature stress rupture strength and high temperature creep resistance, that meet or exceed those of certain Ni-base superalloys.

Abstract: Additions of a first alloy constituent of at least one element from the group consisting of Y, Sc, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, or any combinations of them, and a second alloy constituent of at least one element from the group consisting of C, Si, Ge, Sn and Pb, or any combinations of them, to Ti-base alloys can be employed so as to result in an alloy containing an very fine, substantially homogeneous oxide dispersoid of the first constituent, and produce alloys having improved tensile properties, especially tensile elongation. The dispersoid results from the decomposition of an intermediate phase dispersoid comprising a compound of the first and second constituents which results from rapid solidification of the alloy from a melt. It is preferred that the second alloy constituent should be at a concentration sufficient to form the intermediate phase with all of the element or elements comprising the first alloy constituent.

Abstract: An article having a spallation resistant TBC comprises a metal substrate, such as a high temperature superalloy, and a TBC, such as a coating of yttria stabilized zirconia. The TBC comprises a plurality of plasma-sprayed layers. The TBC has a coherent, continuous columnar grain microstructure, wherein at least one layer has a plurality of continuous columnar grains which have been extended by directional solidification into an adjacent layer. In a preferred embodiment, the coherent, continuous columnar microstructure comprises substantially all of the volume of TBC. A coherent, continuous columnar grain microstructure is also taught wherein at least some of the plurality of coherent, continuous columnar grains which comprise a TBC extend through essentially the entire thickness of the coating.

Abstract: The present invention relates to a process to prepare polysiloxane microspheres with narrow size distribution having a particle size in the range of about 0.5 microns to about 10 microns. The first step involves combining, by weight, an optional anionic surfactant, a polymeric stabilizer, an hydroxide base, and water to form a first aqueous mixture to which is added a silane monomer to form a second aqueous mixture. The second aqueous mixture is then stirred at a temperature of from about 5.degree. C. to about 90.degree. C. for at least about 1 hours to form an aqueous dispersion comprising polysiloxane microspheres. The polysiloxane microspheres upon separation may be optionally washed with water and optionally dried at a temperature of up to about 300.degree. C. The polysiloxane microspheres can be further optionally jet treated to yield polysiloxane microspheres with a narrow size distribution having a particle size in the range of about 0.5 microns to about 10 microns.

Abstract: A process for removing, leaching, or dissolving ceramic cores used to maintain dimensional tolerances for internal passages during metal casting operations of hollow airfoils. The process is especially suited for dissolving porous ceramic cores, such as alumina, silica, alumina doped with oxides, and combinations thereof, that are used in internal passages in turbine airfoils during metal casting operations.

Abstract: 1,1,1-Tris(4-hydroxyphenyl)ethane, a branching agent for polycarbonates, is prepared by the reaction of phenol with 2,4-pentanedione in the presence of sulfuric acid and at least one mercapto sulfonic acid such as 3-mercaptopropanesulfonic acid as promoter. By employing specific proportions of the promoter and sulfuric acid, high product yields can be obtained in relatively short times.

Abstract: Hydroxyaromatic compounds such as phenol are converted to diaryl carbonates by reaction with oxygen and carbon monoxide in the presence of a catalyst package and an added diluent free from active hydrogen. The preferred catalyst packages comprise a Group VIIIB metal or salt thereof, an inorganic cocatalyst, and organic cocatalysts and a bromide or chloride source. The amount of added diluent is an effective amount to improve selectivity to diaryl carbonate. Preferred diluents are diphenyl carbonate and N-methylpyrrolidone.

Abstract: Polyphenylene ethers are decolorized by contact in the melt or in solution with a hydroxy compound containing either another hydroxy group or a double or aromatic bond in a specific location in the molecule. Illustrative decolorizing compounds are benzopinacol, benzoin and acetoin.

Abstract: A method for forming nickel base superalloy articles of manufacture by a combination of hot die forging, isothermal forging and heat treatment below and above the solvus.

Abstract: An adsorption process uses a non-ion-exchangeable adsorbent polymeric resin of a monoethylenically unsaturated monomer such as styrene and a polyvinylidene monomer such as divinylbenzene for the adsorption of organic bases, such amines, amine salts and guanidinium salts, from high ionic strength aqueous solutions. Desorption may be employed for the recovery of said organic bases, and said adsorbent resin may be regenerated.

Abstract: 1,1,1-Tris(4-hydroxyphenyl)ethane in admixture with bisphenol A is obtained by the reaction of 2,4-pentanedione with excess phenol under acidic conditions and in the presence of a mercapto compound as promoter. The products may be separated by extracting bisphenol A with a chlorinated alkane. Purification of the resulting 1,1,1-tris(4-hydroxyphenyl)ethane is achieved by slurrying in and/or recrystallization from methanol-water, optionally with addition of an alkali metal borohydride or dithionite.

Abstract: Quaternary salts having a double helix structure are prepared by the reaction of dihydroxyaromatic compound, preferably a bisphenol, with an alkali metal hydroxide and a quaternary salt, such as a tetraalkylammonium or hexaalkylguanidinium chloride. The quaternary salts and their alkaline hydrolysis products are useful as catalysts in various reactions, including imide formation from bisphenol salts and halo- or nitro-substituted phthalimides and redistribution and equilibration of polycarbonates.

Abstract: Adducts of hydroxyaromatic compounds such as phenol and diaryl carbonates such as diphenyl carbonate are washed with a washing composition comprising a major proportion, typically about 90%, of the hydroxyaromatic compound and a minor proportion, typically about 10%, of the diaryl carbonate.

Abstract: A water exclusion device for underwater arc welding comprises a chamber having flexible gas permeable surface contact member at the lower end. A wire mesh material is the preferred gas permeable material.

Abstract: A superconductive article is made from interconnected superconductive, metallic tapes. The tapes preferably are mechanically joined and electrically interconnected by a plurality of superconductive interconnections that extend between the tapes. The interconnections are formed by overlapping the edges of two tapes and forming a plurality of superconductive welds between the tapes in the overlapping regions. Articles of this invention may be formed from superconductive tapes made from Nb.sub.3 Sn having superconductive interconnections that also include Nb.sub.3 Sn.

Abstract: Systems and methods are disclosed for exhausting and combined exhausting and seasoning of x-ray tubes having glass envelopes for a high performance x-ray system having a rotating anode therein. The methods include providing a glass tubulation having a diameter greater than about 20 mm, then operatively connecting the glass tubulation to the x-ray tube glass envelope, providing a glass sealing cup inside the glass tubulation, the glass sealing cup having a smaller diameter than the glass tubulation, providing a vacuum to the glass tubulation, positioning a heater on the outside of the glass tubulation, heating the anode of the x-ray tube to a temperature inside the x-ray tube glass envelope of about 1500.degree. C., positioning the glass sealing cup inside the glass tubulation proximate the position of the heating means on the outside of the glass tubulation, heating the glass tubulation proximate the glass sealing cup to about 1300.degree. C.

Abstract: Improved methods of exhausting and combined exhausting and seasoning of x-ray tube envelopes for high performance x-ray system having a rotating anode therein which includes providing a glass tubulation having a diameter greater than about 20 mm then operatively connecting the glass tubulation to the x-ray tube envelope, providing a disk inside the glass tubulation, the disk having a smaller diameter than the glass tubulation, providing a vacuum to the glass tubulation; positioning heating means on the outside of the glass tubulation, heating the anode of the x-ray tube to a temperature temperatures inside the x-ray tube envelope of about 1500.degree. C., positioning the disk inside the glass tubulation proximate the position of the heating means on the outside of the glass tubulation, heating the glass tubulation proximate the disk to about 1300.degree. C.

Abstract: Ultracapacitors including at least one cell with two solid, non-porous current collectors, two porous electrodes, preferably of carbon, and a porous separator between the electrodes, employ as electrolytes materials comprising at least one hexasubstituted guanidinium salt. Such salts may be employed in solution in a stable organic liquid such as propylene carbonate, or neat in liquid form. They may be prepared by first preparing a hexasubstituted guanidinium halide and then performing an anion exchange reaction, either with a salt which forms an insoluble halide such as a silver salt or by a liquid--liquid extraction method.

Abstract: A process for the synthesis of polysiloxane emulsions is discussed. The process yields mono modal polysiloxane emulsions, providing control over the particle size and dispersity.