Abstract: A low melting (liquidus temperature <570.degree. C.) rapidly solidified brazing alloy consists essentially of about 14 to 52 weight percent germanium, 0 to 10 weight percent of at least one element selected from the group consisting of silicon, magnesium, bismuth, strontium, lithium, copper, calcium, zinc and tin, the balance being aluminum and incidental impurities. The alloy has the form of a foil and can be used to braze non-heat-treatable rapidly solidified Al-Fe-Si-V alloy foil, sheet plate and tubing to components such as deicing duct, overduct, radiator, heat exchanger, evaporator, honeycomb panel for elevated temperature applications.

Abstract: A plurality of titanium sheets are assembled into a stack. One of the sheets is provided with a stop off material on one surface to prevent diffusion bonding at predetermined positions. The edges of the sheets are welded together and a pipe is welded to the stack to interconnect with the stop off material to form a sealed assembly. The sealed assembly is evacuated. The sealed assembly is heated to evaporate the binder from the stop off and the binder is extracted from the assembly. The pipe is then sealed by two spaced welds. The assembly is heated and externally pressurized to diffusion bond the sheets together. The region of the pipe between the assembly and the first seal and the region of the pipe between both seals collapse to indicate a successful diffusion bond, or one or both regions are uncollapsed to indicate an unsuccessful diffusion bond. An integral structure formed by a successful diffusion bond is then superplastically formed to produce an article.

Abstract: A vacuum pump is first driven to start evacuation from the interior of a furnace. At the time when the furnace pressure reaches 8.times.10.sup.-5 Torr, a heater is driven to start elevating the furnace temperature. Then, at the time when the furnace temperature reaches 565.degree. C. that corresponds to the solidus line temperature for a brazing filler metal of Al - 10% Si alloy containing Mg of 0.6 wt. %, a motor is driven to close a shutter, thereby vacuum brazing aluminum with evacuation control under a high-vacuum level. By controlling the evacuation after reaching a high-vacuum level, the amount of water vapor in the furnace becomes sufficiently small and Mg vapor is highly densified, which permits brazing of satisfactory quality even with a brazing filler metal containing Mg of 1.2 wt. % or less, in combination with use of such a brazing filler metal as having the Mg.sub.2 Si particle size fined to be 5 .mu.m as a typical value through soaking and the thickness of a surface oxide film thinned to be 80 .

Abstract: A process for producing a vacuum interrupter chamber includes placing spacers in bodily contact with a soldering foil and joining the spacers to the soldering foil or fixing them in a displacement-proof fashion on specially made dents in the foil, so that they can be fixed for the purpose of a reliable and simple assembly. Degassing gaps are left between soldering spacers, on which a cover of the interrupter chamber rests. The vacuum interrupter chamber is evacuated in a single furnace cycle and soldered.

Abstract: A low melting (liquidus temperature<570.degree. C.) rapidly solidified brazing alloy consists essentially of about 14 to 52 weight percent germanium, 0 to 10 weight percent of at least one element selected from the group consisting of silicon, magnesium, bismuth, strontium, lithium, copper, calcium, zinc and tin, the balance being aluminum and incidental impurities. The alloy has the form of a foil and can be used to braze non-heat-treatable rapidly solidified Al-Fe-Si-V alloy foil, sheet plate and tubing to components such as deicing duct, overduct, radiator, heat exchanger, evaporator, honeycomb panel for elevated temperature applications.

Abstract: A soldering apparatus is disclosed which comprises a conveyor for moving print circuit boards along a predetermined path, an inert gas-filling chamber provided with a solder tank wherein the print circuit board is soldered in the inert gas atmosphere, primary and secondary, external air shutoff chambers positioned in front of and in rear of the inert gas-filling chamber, respectively. Both primary and secondary chambers are provided respectively with a first shutter having a mechanism for open/close action and capable of isolating the inside of the chambers from external air and with a second shutter having a mechanism for open/close action and capable of preventing release of the inert gas in the inert gas-filling chamber and are connected through a valve to a vacuum tank capable of evacuating the primary and secondary chambers.

Abstract: A ductile oxidation-resistant foil is joined to a titanium alloy substrate by means of a silver-based braze alloy. The braze alloy acts as a bonding agent to join the oxidation-resistant foil to the titanium alloy substrate.

Abstract: The invention relates to a high temperature-resistant composite which consists of at least one part of molybdenum or a molybdenum alloy, and at least one part of graphite, which parts are joined together by means of a zirconium solder. A two-ply interlayer, consisting of a 0.01-0.5 mm thick layer of vanadium, and a 0.1-0.5 mm thick layer of tungsten, tantalum or niobium, is arranged between the part of molybdenum or the molybdenum alloy and the zirconium solder. The layer structure substantially prevents the formation of a eutectic between molybdenum or the molybdenum alloy and the zirconium solder, thereby preventing the reduction of the maximum permissible use temperature of the composite.

Abstract: A thin film eutectic bond for attaching an integrated circuit die to a circuit substrate is formed by coating at least one bonding surface on the die and substrate with an alloying metal, assembling the die and substrate under compression loading, and heating the assembly to an alloying temperature in a vacuum. A very thin bond, 10 microns or less, which is substantially void free, is produced. These bonds have high reliability, good heat and electrical conduction, and high temperature tolerance. The bonds are formed in a vacuum chamber, using a positioning and loading fixture to compression load the die, and an IR lamp or other heat source. For bonding a silicon die to a silicon substrate, a gold silicon alloy bond is used. Multiple dies can be bonded simultaneously. No scrubbing is required.

Abstract: The present invention relates to a soldering machine, comprising: a soldering chamber wherein the soldering process is performed; a first lock chamber connecting to the soldering chamber; a second lock chamber connecting to the soldering chamber; two openings each arranged between a lock chamber and the soldering chamber; two openings each connecting a lock chamber to the outside wherein each opening is closable by a door; means for creating a vacuum in the lock chambers; means for transporting objects for soldering from the outside through the first lock chamber, the soldering chamber and the second lock chamber.

Abstract: A vacuum-insulated, double-walled metal structure comprises inner and outer shells made of a metal and seamed together to form a double-walled structure with a space between them, the space being exhausted of air. At least one of the inner and outer shells is provided with at least one activated foil of a metal selected from the group consisting of copper, titanium and zirconium. The inner shell may be wound with an activated titanium or zirconium foil, and covered by another metal foil selected from the group consisting of copper, aluminum, titanium and zirconium, except for a part of its bottom. The metal foil wound on the metal structure is activated by preliminarily exhausting air from the space so that a pressure therein becomes reduced to a low vacuum of the order of 10.sup.-2 Torr, and then heating the double-walled structure at not less than about 400.degree. C.

Abstract: Articles of aluminum, or of an aluminum alloy, can be brazed satisfactorily, employing an aluminum alloy as the brazing material, by removing any surface oxide layers from bodies comprising the articles, and preforms of the brazing material, simultaneously with providing initial films of zinc, or tin, thereon. Then coatings of silver and/or of gold, or a suitable alloy containing silver or gold, are provided on the articles, and on the preforms of the brazing material, to protect the surfaces of these aluminum containing bodies from reoxidizing. The required brazing operation then is performed in a high vacuum, or in an inert atmosphere. Any oxygen produced inadvertently, for example, by the decomposition of any silver oxide present, is removed before it can contact any aluminum. The zinc or tin, the materials of the coatings, and the aluminum of the bodies, interdiffuse, and this interdiffusion proceeds rapidly when the brazing alloy melts.

Abstract: A method and apparatus for uniting workpieces of silicon-infiltrated silicon carbide with large dimensions includes surrounding each of two silicon-infiltrated silicon carbide workpieces with at least one tightly closing shell in the vicinity of a junction between the workpieces, defining at least one intermediate space between the shell and the workpieces. A vacuum or an inert gas atmosphere is maintained in the intermediate space or spaces. Solder is placed at the junction and the junction is locally heated to soldering temperature for materially bonding the workpieces by soldering at the junction.

Abstract: An infrared detector assembly (10) of the type used in munitions and night vision systems having an improved coldfinger assembly (42). Such detector assemblies (10) include a tubular coldfinger (22) which is surrounded by a vacuum and an end-cap (28) mounted to the coldfinger tube (22) to define a cold end (24) which supports the infrared detector array (30) and related components. In accordance with this invention, the coldfinger tube (22) is a thin-walled titanium cylinder and the end-cap (28) is made of tungsten. The components are metallurgically bonded at the cold end (24) by an active brazing alloy deposited during vacuum furnace brazing. The titanium coldfinger (22) provides the necessary bending stiffness to support cold end components. The tungsten end-cap (28) provides a low distortion, thermally stable focal-plane. The metallurgical bond (46) provides for a hermetic seal which inhibits structural distortion during brazing, and during cyclical cooling of the detector assembly (10).

Abstract: A method of soldering without the need for fluxing agents, high temperature, hydrogen, laser excitation or sputtering techniques. The method uses plasma excitation to remove surface oxides from solder surfaces, thereby eliminating the need for post-soldering cleaning in an accurate and efficient manner, resulting in a higher quality and long term reliability solder joint. In addition, serious environmental problems caused by cleaning solvents are avoided.

Abstract: An ultrasonic transducer and its method of fabrication wherein bonding between an impedance matching layer on one side of a piezoelectric layer and a support layer on the other side of the piezoelectric material is made by providing onto each material a smooth, thin gold film on the smooth surfaces of the layers which are to be in contact with one another in the assembled transducer. The layers are bonded to each other by the gold films under moderate temperature and pressure to form the transducer. Sawing of the impedance matching and piezoelectric layers into a plurality of parallel transducers attached to the support layer forms an array.

Abstract: A method of cladding a base plate of carbon steel, including the steps of plating by electroless deposition the faying surface of the plate slab, positioning a cladding plate, on the the plated faying surface, welding both plates together at three edges to form a seal, attaching a gas reservoir at the fourth side thus forming a sealed subassembly, evacuating the space formed in the subassembly between the two plates of water vapor and oxygen, heating the subassembly to about 1650.degree. to 2100.degree. F. thereby melting the bonding metal alloy, and hot rolling the heated assembly to metallically bond the cladding plate to the steel plate by means of the mechanism of liquid interface diffusion bonding.

Abstract: A process for treating workpieces in a normally closed treatment chamber. The process comprises providing a pressure within the chamber which is less than atmospheric and providing an unsaturated treatment vapor within the chamber. A workpiece is then moved into the chamber to be treated by the unsaturated vapor. The process is particularly suited for the vapor phase soldering of printed circuit boards. The unsaturated vapor in the chamber is heated to a temperature higher than the melting point of the solder used and the circuit boards with solder thereon are passed through the vapor in the chamber to reflow the solder.The invention is also directed toward an apparatus for carrying out the process.

Abstract: A silicon wafer bonding technique is described utilizing low pressures and a dissolvable gas to substantially eliminate voids formed between the bonding surfaces of two wafers.

Abstract: In a method for the continuous manufacture of powder-filled steel tube from steel strip, wherein the strip is moved along a path in which successively the moving strip is formed into an open channel, powder is introduced into the open channel, and the channel is shaped into a tube by further deformation and closure of the strip edges together. To avoid the disturbance of the powder by air currents caused by the strip movement and by the closure of the strip, such air currents arising in the vicinity of the moving strip are removed by suction extraction at the location where the powder is introduced into the open channel.

Abstract: An improved practice for the vacuum brazing of aluminum alloy workpieces in a multi-chamber braze furnace is disclosed. When magnesium-containing aluminum alloys are brazed in a furnace having a braze chamber and adjacent exit chamber, there may be advantage in providing thermal barriers between a load of hot brazed workpieces and the furnace walls of the exit chamber.

Abstract: To avoid having to metallize a bare glass fiber prior to soldering it into a hole of a metal part to obtain a hermetically sealed lead-through bushing, the solder is permitted to shrink onto the glass fiber. This is achieved by either soldering an additional solder body to the metal part outside the hole or providing the wall of the hole with a nonsolderable coating over part of its length. If the metal part is designed as a sleeve, a recess exposing part of the hole causes the solder to firmly shrink on to the bare glass fiber during solidification. The hermetic seal is obtained by arranging the connections of the solder with the metal part and with the glass fiber essentially one behind the other in the longitudinal direction of the glass fiber.

Abstract: The invention provides a method of manufacturing a metal-based composite material, in which the interfacial reaction between an inorganic fiber reinforcing material and a matrix metal such Al or Mg during press forming of the metal-based composite material is suppressed, and the resultant material has an excellent composite state.In the method of the invention, a preform laminate or sandwiched body consisting of the inorganic fiber reinforcing material and the matrix metal is packed in a sealing metal container. After the interior of the container is evacuated, the container is rapidly heated to a temperature higher than the solidus of the matrix metal. Immediately thereafter, while a vacuum pressure is kept unchanged, the container is pressed between a pair of platens kept at a temperature lower than the solidus of the metal, thereby obtaining a composite material of the reinforcing material and the metal.

Abstract: A method for producing a tungsten carbide tip punch includes:(1) preparing a punch rod including a top surface having a cylindrical protrusion;(2) placing on the top surface of the punch rod a tungsten carbide piece having a hardness greater than that of the punch rod and including a bottom surface having a crown-like indentation which opens at the bottom surface and which is capable of being well matched with said cylindrical protrusion at the lowermost portion of the crown-like indentation.

Abstract: The bonding apparatus has a holding device, a pressing device for pressure welding substances to be bonded to each other, and a superhigh vacuum bonding chamber provided with the holding device and the pressing device. A superhigh vacuum bonding preparatory chamber is connected with the superhigh vacuum bonding chamber through a gate valve and a conveyor is arranged for conveying the substances to be bonded between the superhigh vacuum bonding preparatory chamber and the superhigh vacuum bonding chamber. The preparatory chamber is provided with a rotary preparatory table having a plurality of stages for releasably supporting holders for holding the substances to be bonded, the preparatory table being moved to successive positions to register with the conveyor.

Abstract: The instant invention describes a method of repairing heat-resistant alloy parts which have been cracked or otherwise damaged due to exposure of combustion gases from a turbojet engine. The method includes chemically cleaning the surface of the part to remove the layer of contaminants and subjecting the part to a thermochemical treatment to thoroughly clean the cracks and other narrow, damaged areas. A diffusion brazing process is then utilized to fill the cracks or damaged areas.

Abstract: A pre-assembled vacuum switch tube having a clearance between a stationary electrode rod and end plate is firstly prepared by forming an enlarged diameter part in the stationary electrode rod at a position where the rod extends from the end plate to the outside of the vacuum envelope and by arranging at least one piece of plate-like brazing material having a flat surface. The pre-assembled vacuum switch tube is put into a vacuum furnace; the interior of the vacuum switch tube is evacuated through the clearance; temperature in the furnace is elevated to melt the brazing material thereby causing the descending of the enlarged diameter part due to the dead weight of the stationary electrode rod and the vacuum switch tube is sealed by bonding of the end plate and the rod.

Abstract: A method of manufacturing an internally clad tubular product employing a tubular host such as steel, including the steps of plating the internal surface of the tubular host with a low melting point bonding metal alloy, inserting a tubular clad member, such as of nickel base alloy, into the plated tubular host, circumferentially welding one end of the cladding member to one end of the host member directly and welding the other ends in such a manner as to incorporate a metallic gas reservoir, thus forming a subassembly, evacuating the annular space formed in the subassembly between the exterior of the cladding member and the interior of the tubular host of water vapor and oxygen, heating the subassembly to about 1650.degree. to 2000.degree. F. thereby melting the bonding metal alloy, and hot rolling the heated subassembly to metallically bond the cladding member to the tubular host by means of the mechanism of liquid interface diffusion bonding.

Abstract: This invention relates to a method of manufacturing integral melt conveying nozzle probes for injection molding. The generic term nozzle probe is used herein to include both nozzles through which the melt flows centrally and probes which it flows along the outside of. The method includes forming a stainless steel outer member to receive an electrical heater member therein with a longitudinal space therein. A long thin thermocouple sleeve having a closed forward end is located in the space, which is then sealed against leakage by applying a nickel brazing paste to the joints and brazing them in a vacuum furnace. Copper is then cast into the space in a vacuum furnace to provide a metallurgical bond between the highly conductive copper and the heating element, the thermocouple sleeve and the other parts of the nozzle probe. After casting, a long thin drill is inserted into the sleeve to drill through the closed forward end and a predetermined distance into the copper.

Abstract: Chip carriers (10--10) are released from an end of a dispensing means (38) drawn across a holder (22) having a plurality of apertures (28--28) therein, to place a carrier in each aperture. Small solder spheres (58--58) are located in a plurality of dimples (56--56) of a planar plate (40) in arrays that are substantially the same as a plurality of bonding pad arrays (18--18) on the bottom surface of a plurality of chip carriers. A vacuum is applied to the holder (22) to hold the chip carriers (10--10) in the apertures (28--28) as the holder rotates to place the bonding pads (18--18) in contact with the solder spheres (68--68). The solder spheres (58--58) are reflowed by applying heat to form a solder "bump" (68) on each pad (18). The chip carriers (10--10) are then cooled and loaded into a plurality of the tubular members (39--39).

Abstract: The invention relates to a process for the hydrogen-impermeable brazing of austenitic structural steel parts. These are initially loosely joined at soldering points with the addition of definite amounts of solder and soldering agent and subsequently brought to soldering temperature in a furnace under a high vacuum. In order to obtain a satisfactory wetting characteristic, on the one hand, and a good hydrogen resistance, on the other hand, a bicomponent soldering process is provided, with about 1 part by weight of nickel-base solder and about 3 parts by weight of bronze-base solder. The nickel-base solder contains about 1-3% by weight of boron and 2-5% by weight of silicon. The nickel-base solder may amount to at most about 30% by weight of solder. Such soldered joints are used for storage pipes at metal hydride reservoirs.

Abstract: Apparatus for applying a vacuum to a nuclear fuel rod cladding tube's interior through its open end while girth welding an inserted end plug to its other end. An airtight housing has an orifice with a seal which can hermetically engage the tube's open end. A vacuum hose has one end connected to the housing and the other end connected to a vacuum pump. A mechanized device moves the housing to engage or disengage its seal with the tube's open end. Preferably the mechanized device includes an arm having one end attached to the housing and the other end pivotally attached to a movable table; an arm rotating device to coaxially align the housing's orifice with the welding-positioned tube; and a table moving device to engage the seal of the coaxially aligned orifice with the tube's open end.

Abstract: A target body composed of a select target material is attached to a cooling plate for sputtering systems in such a manner that substantially no bubbles, pores or oxide layers are present in the ultimate solder joint between the surfaces joined together. A pre-soldered target body and a corresponding presoldered cooling plate are exposed, in a vacuum, to a temperature above the melting point of the solder utilized so that degasification of the liquified solder occurs and any oxide layers present are decomposed and purged from the solder. Upon cooling in vacuum, the solder resolidifies and excludes any air bubbles, pores or oxide layers. A frame body with a two-step recess, with a lower recess or opening snugly fitting about a cooling plate and an upper opening freely fitting about the solder joint can be used to practice this technique. A subsequent reflow soldering can likewise occur in vacuum at a temperature above the melting point of the solder utilized.

Abstract: This invention relates to an improved method of installing an elongated heater such as a cartridge heater in a molding member such as an injection molding manifold member. First, a bore is drilled into an elongated portion of the manifold member to extend generally parallel to the hot runner passage extending through it and a filler duct is drilled from the top to intersect the bore along its length. The cartridge heater is then inserted into the bore and a filler tube with a base is set on the top in alignment with the filler duct. A brazing paste is then applied around the base of the filler tube and around the terminal portions of the cartridge heater extending from the bore. The manifold member is then heated in a vacuum furnace which brazes the filler tube in position and seals the outer end of the duct against leakage.

Abstract: An electric heating apparatus for heating foods and liquids in a cooking vessel, comprising: a metal upper part, having an upper cooking surface and a lower surface; a metal lower part covering the bottom of the heating apparatus, a sealable space being formed between the upper part and the lower part; and, at least one tubular heating device with a metal covering arranged in the space and having a large flat contact surface for thermally conductively engaging the lower surface of the upper metal part, the space having at least a partial vacuum formed therein, the at least partial vacuum reducing convective heat loss and imparting a concave distortion to the upper metal part which counteracts a convex distortion of the upper metal part due to expansion upon heating, thereby holding the upper metal part substantially flat during heating and maximizing surface contact between the cooking surface and a cooking vessel resting thereon, whereby heat is transferred from the cooking surface to the cooking vessel with

Abstract: The invention provides a novel method for firmly bonding a porous body, e a sintered body prepared by the powder metallurgical techniques with a metal powder, and a fusion-made body, e.g. an iron casting body, hitherto undertaken by the method of pressure welding or diffusion bonding. The inventive method utilizes the principle of infiltration and an infiltrater material is placed at the contacting portion between the porous body and the fusion-made body and heated at a temperature to exceed the melting point of the infiltrater material in vacuum so that the molten infiltrater material is infiltrated into the porous body leading to strong bonding upon solidification to have the porous body and the fusion-made body integrally bonded together.

Abstract: A method of constructing a gas discharge display device in such a manner that contaminants found within the completed display are significantly reduced. The process for assembly of the display incorporates the utilization of a spacer member having a higher melting temperature than the display's perimeter seal and is designed to hold the plates apart without letting certain portions of the sealing material contact the opposing substrate. The use of the spacer member of high temperature material permits a higher temperature to be achieved in the vacuum furnace for evacuating the contaminants produced by out-gassing of impurities in the dielectric and conductive materials as well as the glass substrates and the sealing material. The sealing time for the display after evacuation is shortened to prevent or greatly reduce the possible entrapment of impurities in the display during the higher temperature final sealing step.

Abstract: Disclosed is a single chamber ultra-high vacuum processing system for the oduction of hermetically sealed quartz resonators wherein electrode metallization and sealing are carried out along with cleaning and bake-out without any air exposure between the processing steps. The system includes a common vacuum chamber in which is located a rotatable wheel-like member which is adapted to move a plurality of individual component sets of a flat pack resonator unit past discretely located processing stations in said chamber whereupon electrode deposition takes place followed by the placement of ceramic covers over a frame containing a resonator element and then to a sealing stage where a pair of hydraulic rams including heating elements effect a metallized bonding of the covers to the frame.

Abstract: Method for encapsulating components in cases, which includes connecting a gold wire to an aluminum surface, subsequently closing the case by welding in a vacuum, and tempering the case in a hydrogen-containing atmosphere and an encapsulation produced by the method.

Abstract: Method for making a tube for a cracking plant, by providing an inner tube, placing a reinforcement about said inner tube, said reinforcement having transverse openings or passages, placing an outer tube coaxially about said inner tube and said reinforcement, bonding together by pressure or fusion welding, said inner tube and said outer tube through said openings or passages in said reinforcement.

Abstract: An improved welding fume and spark trap includes a cannister and an inlet and outlet plenum for connection with an air filtration suction system designed to remove soot, fumes, and other particles from a welding area. The trap includes an internal baffle for reducing the velocity of the air stream passing through the trap, in this way promoting settling of particles suspended within the air stream into water contained within a water chamber defined by the bottom portion of the cannister.

Abstract: Disclosed is a semi-automatic processing system for the production of components requiring the deposition of metallization and assembly in an oil free ultra-high vacuum environment. The system is comprised of a plurality of interconnected tubular high vacuum chambers for separately performing ultra-violet cleaning, bake out, plating and sealing of, for example, quartz crystal resonator units, in an in-line configuration adapted for continuous cycle processing of components. The major elements of the system include: (a) a belt type transport which is adapted to convey one or more components through the respective chamber and into an adjoining chamber through an intermediate gate valve; (b) manipulators for handling the component parts inside the vacuum chambers; (c) long life highly directional evaporation sources for evaporated metal deposition on selected component parts; and (d) a sealing apparatus for hermetically sealing the components after evaporation without exposure to atmosphere.

Abstract: A vacuum insulated container is constituted by a double-walled receptacle wherein the space between the walls is substantially evacuated to provide vacuum insulation. The outer wall is provided with an opening therein which is used during manufacture to provide access to the space between the walls so that the space may be evacuated. A stopper- or plug-like portion fills the opening after the container has been evacuated and is permanently joined or bonded to the surfaces of the opening thereby providing a sealing to maintain the vacuum in the space between the walls.

Abstract: Two parts, such as a quartz part and piezo-electric part, are indirectly connected to one another by applying relatively thin metallic layers having a thickness of about 0.5 nm to 55 nm under vacuum conditions onto the surfaces of such parts to be joined and then without ventilation of the vacuum-chamber contacting the free surfaces of such metallic layers with one another under the maintained vacuum conditions whereby a substantially permanent bond is formed between such layer.

Abstract: Metal/ceramic abradable seals of the type used in jet aircraft are improved by maintaining a temperature differential between the metal/ceramic composite and the cooler substrate during cooling from the brazing temperature.

Abstract: An aluminum-silicon base brazing alloy contains between 4 and 20 percent by weight of silicon and between 0.0001 and 1.0 percent by weight, preferably between 0.005 and 0.1 percent by weight, of at least one of the elements sodium, potassium and lithium. Optionally, the brazing alloy may further include between 0.01 and 10 percent by weight, preferably between 0.05 and 2 percent by weight, of at least one of the elements bismuth, strontium, barium and antimony as well as between 0.00001 and 1.0 percent by weight, preferably between 0.0002 and 0.1 percent by weight, of beryllium. The remainder of the alloy consists essentially of aluminum and impurities conditioned by production of the brazing alloy. The alloy is used for the fluxless brazing of aluminum-containing articles in substantially non-oxidizing atmospheres.

Abstract: An apparatus is provided comprising three elongated vacuum chambers arran in line one after another whereby a component carrying means may be transferred successively from one chamber to another. Of these three chambers the first and third comprise air locks and the intermediate chamber contains heat sealing means whereby components undergoing sealing may be soldered under vacuum. By providing a permanent magnet on each end of the component carrying means this may be shifted between vacuum chambers by external application of a magnet. The overall length of the apparatus is reduced since only three chambers are required and the intermediate chamber may be made shorter than would be the case where no such arrangement is provided.

Abstract: The present development is directed to a method for joining metal at relatively low temperatures by solid-state bonding. Planar surfaces of the metal workpieces are placed in a parallel abutting relationship with one another. A load is applied to at least one of the workpieces for forcing the workpieces together while one of the workpieces is relatively slowly oscillated in a rotary motion over a distance of about 1.degree.. After a preselected number of oscillations, the rotary motion is terminated and the bond between the abutting surfaces is effected. An additional load may be applied to facilitate the bond after terminating the rotary motion.

Abstract: A method of making a solar absorber panel is disclosed in which mild steel sheets are provided with a pattern of recesses such that when the sheets are superimposed, an internal hollow fluid heat transfer passage system is formed thereby including inlet and outlet manifolds joined by connecting passages. A metallic sealing material having a lower melting point than the sheets is placed in the recesses, the sheets are superimposed and the structure is peripherally welded to form a gas-tight envelope. The envelope is purged of air, partially internally evacuated and the edges of the internal passages sealed by heating the assembly above the melting point of the sealant material. The vacuum drawn on the envelope insures a tight seal between all passages as it allows external ambient air pressure to force the sheets together.

Abstract: A seal-welded pipe joint mechanically braced by a clamp for preferred use in handling toxic and radioactive materials is disclosed together with a process for joining the same. The joint comprises a pair of abutted male frustroconical skirts, each attached integrally to the pipe segments to be joined and confronting each other at opposed mating and finished surfaces which define a sunken ridge at their periphery. A uniform continuous seal weld of relatively slight penetration seals the opposed mating and finished surfaces at the ridge. The pipe joint is physically secured by a plurality of, for example, three female frustroconical segments forming a circumscribing collet which is circumferentially clamped to the skirt. When the collet is clampd over the abutted skirts with seal weld there between, the mating and finished surfaces are compressd together, relieving the seal weld of shearing and normal stresses.