Abstract: A method of fluxless brazing of aluminum parts is disclosed. Gaseous species, such as O.sub.2 and H.sub.2 O, which inhibit wetting are controlled by rapid heating (at least 100.degree. C./min) through a critical temperature range (such as 400.degree.-590.degree. C.) during heat-up to brazing temperatures. The formation of porosity through the oxide film and the collection of a promoter and wetting agent at the interface with the oxide film will thus occur simultaneously precluding disruption of wetting action by gaseous O.sub.2 or H.sub.2 O. Wicking of the wetting agent through the film porosity in the critical temperature range will then take place because of the limited time available for the reaction of gaseous O.sub.2 and H.sub.2 O with the film to form a duplex oxide. Heating may be carried out in a vacuum of 10.sup.-3 Torr or less or in an inert atmosphere with pulsed heating, provided the critical heating rate is observed in said critical temperature range.

Abstract: Processes and compositions for soldering aluminum-containing workpieces wherein the solder contains components which lower the surface tension and the viscosity of the molten solder, and which lower the interfacial tension between the solder and the aluminum-containing workpieces. Useful components are bismuth, strontium, barium and antimony. The solder may be used with or without flux.

Abstract: The invention relates to a moving sealing device of the type comprising a chamber movable along a pre-determined path along a wall with which it is tightly connected on a closed contour, and means for providing an opening through the wall within said contour and for causing said opening to progress along the pre-determined path of the chamber simultaneously with the latter.

Abstract: A narrow crevice in a Ni-base superalloy article is repaired by first removal of a complex oxide of at least one metal selected from Al and Ti, by treatment of the oxide in the crevice with gaseous active fluoride ions in a non-oxidizing atmosphere at a temperature at which the oxide will react with the fluoride ions under the conditions around the oxide. The crevice is then repaired in a subsequent step such as by filling with metal or pressure bonding.

Abstract: A method of high temperature assembly of similar or different metallic, nonmetallic or partially metallic components without any direct contact with a cleaning flux, by means of an added metal or alloy with a melting point below that of the most fusible component, characterized in that the components to be assembled and the added metal or alloy are brought to a temperature at least equal to that required to melt the added metal or alloy, in a chamber from which air is substantially evacuated and which contains one or more halogens in the free or combined state, at least a fraction of these free or combined halogens being or passing into the gaseous state for at least part of the heating time.

Abstract: This invention discloses a vacuum power interrupter, having high reliability of vacuum sealing, which is manufactured by using the most suitable brazing material whose main component is Cu or Au for each component of vacuum power interrupter in one brazing process or in two brazing processes.

Abstract: Method and apparatus for filling viscous dampers in which the method comprises assembling a damper housing with an inertia weight placed loosely therewithin and a housing top having a single aperture therein and adapted to provide a complete closure for the inertia weight, placing the assembly in a vacuum chamber equipped with an electron beam welding device and means for effecting relative movement between the assembly and the electron beam welding device, and inserting a valve and fitting sealingly within said aperture with the valve in an open position, evacuating the vacuum chamber to provide a vacuum within the chamber and within the damper assembly, effecting movement between the assembly and the device to sealingly weld the top to the damper housing, closing the valve, attaching means for supplying a viscous fluid under pressure to said valve, removing the valve from the damper assembly, and welding a plug within the aperture to sealingly retain the fluid within.

Abstract: A method of making a composite diffusion bonded structure, comprising a honeycomb panel portion made up of a honeycomb core sandwiched between two face sheets, and a load carrying structural member bonded thereto. The honeycomb core, face sheets and structural member are preassembled in a vacuum furnace so as to permit exposure of the surfaces which are to be diffusion bonded. A vacuum is drawn and the assembly is heated to near diffusion bonding temperature with the bonding surfaces still exposed to the vacuum environment. Thereafter, the bonding surfaces are brought into contact with very moderate pressure, and are maintained at a temperature and pressure sufficient for diffusion bonding. The assembly is then cooled, with the result being a substantially unitary diffusion bonded structure.

Abstract: A method is described for joining first and second surfaces by depositing a layer of metal on the first surface, preparing the second surface to expose fresh metal, placing the deposited metal and the exposed metal in contact, and applying sufficient pressure to join the surfaces, all done in a protective environment, such as vacuum. Also described is a related apparatus comprising an evacuable chamber, an electron-beam heated vapor source, and a pair of rollers for contacting and applying pressure to join the surfaces.

Abstract: A method of fabricating large cylindrical sections of titanium or other metals for applications such as pressure hulls from cylindrical segments wherein mated segments are capped off and evacuated, atmospheric pressure being used to force the mating surfaces together during diffusion welding.

Abstract: An improved method for brazing aluminum and alloys of aluminum in which at least one of the surfaces to be joined is coated with a controlled quantity of metallic manganese which is effective during the high temperature vacuum brazing operation to promote a wetting and flow of the brazing filler metal between the surfaces to be joined and a penetration of the tenacious aluminum oxide film thereon, thereby producing a substantially uniform and high strength bond.

Abstract: A method for brazing nickel to aluminum in a vacuum and product produced thereby. The outer surface of the aluminum member to which the nickel member is to be brazed is precoated with a layer containing silicon and magnesium. The nickel and aluminum members are placed together in an oven at reduced pressures and heated to a temperature of approximately 593.degree.C cracking the oxide coating upon the aluminum sheet. The presence of magnesium and silicon in the surface of the aluminum sheets makes possible an excellent braze with a large filleted area. The process may be further adapted for brazing other metal components to aluminum by first precoating the component with nickel.

Abstract: 1. A method for joining beryllium to beryllium by diffusion bonding, comprising the steps of coating at least one surface portion of at least two beryllium pieces with nickel, positioning a coated surface portion in a contiguous relationship with an other surface portion, subjecting the contiguously disposed surface portions to an environment having an atmosphere at a pressure lower than ambient pressure, applying a force upon the beryllium pieces for causing the contiguous surface portions to abut against each other, heating the contiguous surface portions to a maximum temperature less than the melting temperature of the beryllium, substantially uniformly decreasing the applied force while increasing the temperature after attaining a temperature substantially above room temperature, and maintaining a portion of the applied force at a temperature corresponding to about maximum temperature for a duration sufficient to effect the diffusion bond between the contiguous surface portions.

Abstract: A liquid interface diffusion process for bonding titanium or titanium alloys wherein at least one of the titanium type materials to be fayed is sequentially plated with a total weight of from between 1 and 5 gms/ft.sup.2 of honeycomb core of layers of copper and nickel or an alloy made therefrom. The faying surfaces are then held together to maintain position on alignment, placed in a protective atmosphere, the temperature of the materials are then raised at a controlled rate causing sufficient solid state diffusion to occur and a liquid to form continuing to increase the temperature to a predetermined level and holding at this temperature until a solidification occurs and sufficient additional solid state diffusion occurs producing a desirable dilution of bridge material and titanium at the joint, and then reducing the temperature at a controlled rate to a lower temperature to complete the bonding cycle.

Abstract: Method and apparatus for filling viscous dampers in which the method comprises assembling a damper housing with an inertia weight placed loosely therewithin and a housing top having a single aperture therein and adapted to provide a complete closure for the inertia weight, placing the assembly in a vacuum chamber equipped with an electron beam welding device and means for effecting relative movement between the assembly and the electron beam welding device, and inserting a valve and fitting sealingly within said aperture with the valve in an open position, evacuating the vacuum chamber to provide a vacuum within the chamber and within the damper assembly, effecting movement between the assembly and the device to sealingly weld the top to the damper housing, closing the valve, attaching means for supplying a viscous fluid under pressure to said valve, removing the valve from the damper assembly, and welding a plug within the aperture to sealingly retain the fluid within.