Abstract: A method of decreasing a cycle time of a brazing process is provided. The method includes arranging each of first and second pairs of braze parts together, each of the first and second pairs of the braze parts having braze material interposed between the braze parts, stacking the first and second pairs of the braze parts to form a stack, interposing pyrolytic graphite (PG) between the first pair of the braze parts and the second pair of the braze parts in the stack and heating the first and second pairs of the braze parts to a brazing temperature to braze the braze parts of each of the first and second pairs of the braze parts together.

Abstract: An aluminum alloy precursor composition and method for fusion processing is provided which reduces hot cracking, improves compositional control, reduces porosity, and/or enhances the mechanical properties of the fusion processed article. The precursor material and fusion process using the same may be utilized for forming an article that meets compositional specifications for aluminum 6061 alloy, while minimizing defects and meeting desired strength and ductility requirements. The fusion process may include a leading energy beam for liquefying the precursor material to form a melt pool, and a trailing energy beam directed toward a trailing region of the melt pool. The trailing energy beam may be configured to enhance agitation and/or redistribution of liquid in the melt pool to prevent hot cracking, reduce porosity, or improve other characteristics of the solidified part. The method also may improve processing parameters, such as adjusting vacuum level to prevent volatilization of alloying elements.

Abstract: An aluminum alloy precursor composition and method for fusion processing is provided which reduces hot cracking, improves compositional control, reduces porosity, and/or enhances the mechanical properties of the fusion processed article. The precursor material and fusion process using the same may be utilized for forming an article that meets compositional specifications for aluminum 6061 alloy, while minimizing defects and meeting desired strength and ductility requirements. The fusion process may include a leading energy beam for liquefying the precursor material to form a melt pool, and a trailing energy beam directed toward a trailing region of the melt pool. The trailing energy beam may be configured to enhance agitation and/or redistribution of liquid in the melt pool to prevent hot cracking, reduce porosity, or improve other characteristics of the solidified part. The method also may improve processing parameters, such as adjusting vacuum level to prevent volatilization of alloying elements.

Abstract: High-current, compact, flexible conductors containing high temperature superconducting (HTS) tapes and methods for making the same are described. The HTS tapes are arranged into a stack, a plurality of stacks are arranged to form a superstructure, and the superstructure is twisted about the cable axis to obtain a HTS cable. The HTS cables of the invention can be utilized in numerous applications such as cables employed to generate magnetic fields for degaussing and high current electric power transmission or distribution applications.

Abstract: High-current, compact, flexible conductors containing high temperature superconducting (HTS) tapes and methods for making the same are described. The HTS tapes are arranged into a stack, a plurality of stacks are arranged to form a superstructure, and the superstructure is twisted about the cable axis to obtain a HTS cable. The HTS cables of the invention can be utilized in numerous applications such as cables employed to generate magnetic fields for degaussing and high current electric power transmission or distribution applications.

Abstract: An elongated current limiting composite material comprising one or more high-temperature superconductor filaments and a second electrically conductive member, which may include a sheath of high bulk resistivity surrounding the filament. The current limiter exhibits dissipation in the range of 0.05-0.5 V/cm at currents of 3-10 times the operating current, thereby minimizing fault currents and improving recovery capability.

Abstract: Disclosed are economical methods and apparatus for high throughput pressure infiltration casting. Methods of the invention use a mold vessel as an evacuation chamber along with an evacuation cap to produce superior quality near-net shape finished cast parts with low porosity. Other methods of the invention use an improved heat transfer technique for directionally solidifying molten infiltrant at an increased rate to increase further the throughput of the pressure infiltration casting cycle. The invention also provides apparatus for practicing methods for high throughput pressure infiltration casting. One embodiment of an apparatus of the invention is a removable evacuation cap, often used in conjunction with a fill tube. Another apparatus embodiment is an evacuation cap coupled to a mold vessel which is used as an evacuation chamber.

Abstract: A superconducting article having a high bulk sheath resistivity, and methods of manufacture of such an article. High-temperature superconductor filaments are disposed in a ductile matrix comprising a high silver content. The matrix is then coated with a solute and heated to a temperature high enough to allow the solute to diffuse into the matrix, but not high enough to allow substantive degradation or poisoning of the superconductor. After diffusion and cooling, the matrix comprises a silver alloy having a higher bulk resistivity than the pure silver.

Abstract: A mold cavity in a mold vessel is evacuated. A charge of molten infiltrant is transported into the mold vessel while the vacuum is maintained in the mold cavity. Pressure is applied to the molten infiltrant to move the molten infiltrant from the mold vessel into the mold cavity. The molten infiltrant is cooled in the mold cavity to solidify the infiltrant. A fill tube can be used to transport the infiltrant to the mold vessel.

Abstract: Oxygen tension of tissue in a living subject may be determined non-invasively by a method which involves: administering to a living mammalian subject a biologically compatible perfluorocarbon emulsion in an amount effective to generate a measurable .sup.19 F spectrum under .sup.19 F NMR spectroscopy; allowing sufficient time to elapse for substantially all of the perfluorocarbon emulsion to be cleared from the vascular system of the subject, with a portion of the perfluorocarbon emulsion becoming sequestered in tissue of the subject; subjecting the tissue in which the perfluorocarbon emulsion has become sequestered to a .sup.19 F magnetic resonance spectroscopy procedure in which simultaneous measurements are made of spin-lattice relaxation rates for at least two separate resonances of the perfluorocarbon emulsion; and comparing the at least two spin-lattice relaxation rates measured in the .sup.