Abstract: There is disclosed a method of producing a bimetal for use as a material for a plain bearing. A copper alloy powder is placed on a back steel. The back metal and the copper alloy powder are preheated to a temperature near a Curie point of the steel in a reducing atmosphere by high-frequency induction heating. The preheated back steel and copper alloy powder are heated to a temperature of 770.degree. C. to 950.degree. C. in one of an electric resistance furnace and a gas furnace in a reducing atmosphere so that the copper alloy powder is sintered to form a sintered copper alloy layer and at the same time the sintered copper alloy layer is bonded to the back steel, thereby producing the bimetal.

Abstract: A process for brazing non-ferritic steel surfaces such as nickel chromium or stainless steel to which a suitable brazing alloy such as copper has been mechanically attached which includes the steps of instantaneously elevating the surface of the stainless steel to a brazing temperature while maintaining the material in a humidified gaseous atmosphere consisting essentially of a non-reactive carrier gas and a reactive gas present in sufficient concentrations to achieve fluxing; maintaining the surface temperature of the steel for an interval sufficient to permit fusion between the selected metal and the non-ferritic steel surface; after metal fusion has been achieved, allowing the resulting fused metal material to cool to a first lowered temperature in a controlled non-oxidative atmosphere at a rate which retards the formation of fine-grained steel crystals in the metal; and after reaching a metallurgical transformation point, rapidly cooling the fused metal in a controlled atmosphere to a temperature below wh

Abstract: The turbine blade tip clearance control system presently used with existing turbine blade uses an abradable seal material with a conventional squealer tip. Others use a thin, coating added to the tip of the blade. The present turbine blade tip control system minimizes the problem of controlling the clearance between the blade and the shroud and overcomes the problem of wearing away of the thin coating added to the tip by using a rub tolerant, high-temperature seal material coating on a turbine shroud and a turbine blade made of at least two materials. The combination of the coating and an outer tip being of a different material than the metallic body also minimizes the problems associated with the burning of dirty fuels. The blade has a metallic body of high strength and the outer tip has a strength less than the strength of the body and made of a material resistant to oxidation, sulfidation and thermal fatigue at operating temperatures. The outer tip has a radial length "L" at least 1 mm in length.

Abstract: A method for facilitating the assembly of a structural panel and for preventing the sag thereof comprises the step of placing the structural panel (2), comprising an outer plate (6) and an underlying skeleton framework (7), upon longitudinally extending support beams (B') which interconnect the upper ends of laterally spaced rows of longitudinally spaced support columns (C) which extend upwardly from a floor support surface (F). A mobile radiation heating element truck (4), movable upon laterally spaced rails (8) by means of casters (11), includes radiation heating elements (12).

Abstract: In order to solder a silicon substrate on a supporting plate, an aluminum thin plate is inserted therebetween as a solder metal layer. An assembly thus obtained is heated to 580.degree. C. which is higher than the recrystallization temperature 264.degree. C. of the aluminum thin plate but is lower than the eutectic reaction temperature 585.degree. C. of the interface between the silicon substrate and the aluminum thin plate. After the assembly is held at 580.degree. for twenty minutes, the assembly is further heated to 610.degree. C. in order to melt the aluminum thin plate into which silicon atoms are diffused. The aluminum thin plate changes uniformly to an eutectic layer consisting of silicon and aluminum, whereby the silicon substrate is soldered on the supporting plate.

Abstract: A method is disclosed for brazing without filler metal two components, of which at least one is an Al alloy. According to the method, prior to brazing, at least one Al alloy component is maintained in a region of temperatures included between the temperature of solvus T.sub.v of the alloy and 2/5 of temperature of fusion (solidus) T.sub.s of the alloy, expressed in degrees Kelvin, for a sufficient period of time. After this treatment, which may or may not be isothermal, the alloy is suitable for brazing in a domain of temperatures included between the temperature of fusion T.sub.e of the most fusible eutectic corresponding to the equilibrium diagram of the constituents of the alloy, and that of the solidus of the alloy. The method permits the realization of perfectly homogeneous brazed seams for alloys considered not to be brazable.

Abstract: A method for weld repair and rebuilding of worn and cracked diesel engine cylinder heads of the pot-type is used in railway locomotive diesel engines and the like. The method involves carefully controlled preheating, welding and cooling steps.

Abstract: A reflow soldering method and the apparatus thereof is disclosed, wherein an air flowing fan is provided at the bottom of the apparatus, that is, below a work transporting conveyor so as to produce a minus pressure to draw or pull air into the apparatus in a manner that the drawn air may flow in a constant volume and at a constant speed from up to down through a predetermined path and flow down through a heater provided in the path to be heated up substantially to a set temperature of the heater. The heated air further flows down to contact a work such as a base board having electronic parts mounted thereon and transported by the conveyor and heat up the work.

Abstract: A preventive method for thin-gage plate deformation in manufacturing flat plate welded structures, which are constructed by welding thin-gage plates and frames and are used for side-plates, etc. in rolling stocks. The said method comprises preheating the whole thin-gage plate in a heating box for thermal expansion, and welding the thin-gage plate and the frame as the plate is expanded.

Abstract: A solder paste mixture for soldering surface mount devices to a circuit board using a reflow soldering process which utilize a vapor phase furnace. The solder paste mixture has a metallic content which is 63% tin and 37% lead. The metallic content of the paste consists of 150 micron particles of 100% tin and 150 micron particles of an alloy of 10% tin and 90% lead. Included in the process of soldering components to the circuit board is the step of prebaking the circuit board with solder paste and components in their proper place on the board.

Abstract: Apparatus for facilitating the assembly of a structural panel and for preventing the sag thereof comprises an upstanding support structure in the form of laterally spaced rows of longitudinally spaced columns (C) which extend upwardly from a floor support surface (F). Longitudinally extending support beams (B') interconnect the upper ends of the support columns (C), and the structural panel (2) comprising an outer plate (6) and an underlying skelton framework (7) is supported upon the support beams (B'). A radiation heating element truck (4), movable upon laterally spaced rails (8) by means of casters (11), include radiation heating elements (12) mounted upon a support panel (5) whereby the truck (4) is movable between first and second operative positions or stages (A, B).

Abstract: A method for vapor phase soldering components onto a PWB onto which solder has been previously deposited includes the steps of applying a fluxing agent on the PWB and introducing the PWB into a vapor phase environment. The application of flux is a multi-step process which includes a sequential application of flux to the PWB. The vapor phase environment defines a temperature gradient between approximately ambient and the temperature of a saturated vapor of a first selected fluid which defines a primary saturated vapor phase with a boiling point which is greater than the melting point of solder. A second fluid having a boiling point which is lower than the first fluid is utilized to generate a secondary vapor blanket in order to prevent excessive loss of the fluid defining the primary vapor phase. The PWB is heated according to a controlled process in which the temperature of the PWB is continuously monitored.

Abstract: A part and method for repairing a high velocity fluid flow machine part, for example a turbine blade comprises an insert which may be made from a piece of material the same as the turbine blade and prior to attachment to the blade has an edge region hardened by any suitable means, for example induction hardening, the insert then being secured to the blade by welding or brazing, the weld or braze material being of a relatively soft nature to provide a cushion between the insert and the blade so as to minimize the occurrence of stress corrosion cracking.

Abstract: Method for reflow soldering respectively desoldering of circuit boards by using infrared radiation from radiator groups in a furnace. The circuit boards are introduced into the furnace on a timed belt or work piece carrier and maintained motionless during the prewarming, soldering respectively desoldering and cooling down phase. For prewarming for a first given time the radiator groups are operated with reduced operating current. For reflow soldering respectively desoldering the operating current of the radiator groups is switched for a second given time to a maaximum given stage and subsequently turned off completely. The soldered respectively desoldered circuit boards are cooled in a laminar air stream from ventilators for drawing off the solder vapors; the ventilators are initially operated with reduced number of rpms until the solder solidifies and then at the maximum number of rpms. Subsequently, the circuit boards are moved out of the furnace.

Abstract: In the process of braze attachment of electronic package members, such as attaching metallic coated connector pins to a multilayer ceramic substrate, contact areas of the substrate are formed by sequential coatings of molybdenum and nickel, which are heated to diffuse the nickel. A pure gold paste is applied by screen printing, for example, followed by the step of firing to burn out the paste binder and to sinter the pure gold particles onto a dense low porosity structure. The sintering operation converts the Ni film into a continuous Au-Ni solid solution. During pin braze, Ni-Sn intermetallics are dispersed in a gold rich matrix of the Au-Ni solid solution.

Abstract: A method for forming monolithic structures from a plurality of aluminum or aluminum alloy sheets is provided which integrates a method for producing a selective fine grain structure in each of the sheets, with roll bonding and superplastic forming. The sheets are subjected to isothermal aging or controlled slow cooling to obtain a desired grain size in each of the respective sheets. Different heating and cooling treatments can be individually applied to each of the sheets so that the sheets can be tailored to have a fine grain or a coarser grain. Stop-off material is applied at selected areas of the sheets, and the resulting stack of sheets is subjected to cold roll bonding to bond adjacent surfaces of the sheets where stop-off material has not been applied. The roll bonding step also serves to plastically deform the sheets. The roll-bonded stack of sheets is then subjected to rapid heating for recrystallization of one or more of the sheets into a fine grain structure.

Abstract: A component made of nodular cast iron is joined to a component made of steel by means of fusion welding, a Fe alloy containing 2 to 4% by weight of silicon and seeding materials for the purpose of globular carbon precipitation in the welding zone being used as filler. Advantageously, the nodular cast iron component is provided beforehand with a build-up welding with Si-alloyed filler or with an unalloyed filler now alloyed with such a Si-alloyed filler, whereupon the weld joining to the steel component can be carried out with conventional iron electrodes.Preferred Si-alloyed filler:C=0.01-0.12% by weight,Mn=0.2-1.5% by weight,Si=1-4% by weight,Al=0.005-0.1% by weight,Mo=0.2-0.7% by weight,Ce=0.0001-0.02% by weight,Mg=0.0001-0.01% by weight,Zr=0.01-0.7% by weight,S=0.006% by weight max.,P=0.01% by weight max.

Abstract: Pieces of metal are joined with silver material in a two-stage heating process. In one application, a brazed porous coating of metal particles on a metal substrate of a device is formed by interposing a silver material between the substrate and the particles, and placing the particles onto the substrate. The device is heated to a first temperature slightly below the melting point of the silver material, then briefly heated to a second temperature above 1100.degree. C. to rapidly melt the silver material to wet the particles and substrate and to generate alloying among the silver material, the particles, and the substrate. The device is allowed to cool to solidify the alloy and unite the particles and substrate to form a porous coating on the device. Also disclosed are a prosthetic device having a metal shaft for insertion into a bone canal, and a porous coating of metal particles brazed to the metal shaft by a silver material.

Abstract: An apparatus for continuous production of seam-welded steel tubing is proposed. The apparatus includes a series of shaping rolls for shaping a strip taken out from a strip coil into a tubular intermediate product, the roll series including a finpass roll group. The tubular product is subjected to seam welding under the action of a seam welder. Before arrival at the welder, a substantial main part of the preformed tubing with exception of opposing edge zones thereof is subjected to heating by a heater compensate for excess compressive stresses induced in the edge zones, while these zones are subjected to cooling by a cooler for avoiding otherwise formation of disadvantageous edge wavings which would otherwise occur.

Abstract: A cam follower and process of manufacture in which a hardenable cast iron reaction member is welded, as by high energy beam welding, to the end of a tubular, mild steel base member. The surface of the reaction member may be decarburized before welding. The weld is preferably characterized by austenitic properties and is formed by an alloy of nickel with the metal of the cam follower members.

Abstract: An improved solder reflow system for mass joining with solder electrical and electronic components affixed on a circuit board is provided. The system employs a combination of IR heating, recirculating forced hot air heating, and focused forced hot air heating to achieve solder reflow at throughput speeds and soldering quality not heretofore achievable.

Abstract: An automatic soldering apparatus and method thereof is described, wherein a flux is heated up to a predetermined temperature, and is then contacted to a face of a printed base board to thereby coat the base board and to simultaneously heat the latter with the heated flux and then the heated base board is contacted to a melted solder, and wherein provided in combination are apparatus for transporting the base board, apparatus for coating the base board with the heated flux, the flux coating apparatus including a tank in which the flux is stored, heating elements for heating the flux up to a predetermined temperature such that the heated flux is coated on the face of the base board, the heated flux simultaneously heating the base board when the latter is transported to the flux storing tank, and apparatus for soldering the flux coated and heated base board, the soldering apparatus including a tank in which a melted solder is stored which is contacted to the base board when the latter is transported to the tank,

Abstract: A typical method for bonding a die to a substrate includes the steps of placing a solder preform onto the substrate, contacting the die to the preform and applying heat sufficient for the solder to flow and wet the substrate and die forming a bond therebetween. The present invention comprises heating the substrate and preform to a temperature below the melting point of the solder preform and thereafter maintaining this temperature while applying pressure to the preform sufficient to substantially reduce the thickness of the preform and to cause the preform to adhere to the substrate prior to contacting the die thereto.

Abstract: A method for manufacturing a frame for an electric motor including a frame main body and a metallic member welded to the outer surface of the frame main body is disclosed. After metallic members such as cooling fins are attached to the outer surface of a hollow cylindrical frame main body by projection welding which results in distortion of the frame main body due to radial expansion, sizing is applied to the inner surface of the frame main body by applying a radially outward force from inside of the frame main body to remove the distortion and expand the frame main body so that the inner surface of the frame main body defines a true circle.

Abstract: A process for brazing a sleeve within a tube which is resistant to longitudinal expansion is disclosed herein. In the first step of the process, a thermally induced radial expansion is induced in the tube in a first longitudinal section of the tube which does not include the ring of brazing alloy which circumscribes the sleeve. In the second step of the process, a brazing heat is applied across the longitudinal section of the tube which does include this ring of brazing material. The residual tensile stress created by the thermally induced radial expansion in the tube avoids the creation of gaps in the braze joint between the sleeve and the inner walls of the tube. This process is particularly useful in creating high-quality braze joints in sleeving operations in nuclear steam generators, where the heat exchange tubes which need to be sleeved may be partially or completely prevented from expanding in the longitudinal direction due to sludge deposits in the generator.

Abstract: After the support of not-noble metal has suitably been heated and before and during the application of a tablet of soldering material destined to receive the semiconductor chip, the soldering area is engaged by a reducing gas flame (for example, 20% hydrogen and 80% nitrogen at a temperature lower than 570.degree. C.), which eliminates any oxidation products. The soldering is thus of very good quality without using the normal plating of noble metal.

Abstract: A method of repair of an article incorporating the application of considerable thermal energy, e.g. a welding operation, requires heating of the article both in the repair area and surrounds wherein the heating of the repair area and surrounds is carried out by flexible heating mats and wherein fixing means are used to securely fix the heating mats to the article, which fixing means may readily release at least a part of the heating mats whereby that part may be folded back or otherwise removed from the repair area to allow the repair step to be carried out. After repair, that part of the heating mats removed from the repair area may be replaced.

Abstract: A method of repairing turbine blades including a repair step which involves the application of substantial thermal energy to the blade such as a welding or brazing operation includes a pre-heating step in which the blade is heated to a predetermined temperature in a controlled manner. The controlled heating may be continued both during the repair step involving the application of substantial thermal energy and after the repair step in order to minimize stress in the blade due to the application of considerable thermal energy to the blade.

Abstract: The invention concerns preventing oxidation of printed circuit board metal surfaces as a result of heat produced in a solder bath arrangement and reducing thermal stress defects from occurring in the circuit carrier being soldered. An enclosed reaction chamber is provided with the solder bath and supplied with a pressurized atmosphere of inert gas which gas seals the reaction chamber from ambient air. The inert gas is discharged from jets against the solder side (the connector post side) of the printed circuit boards at a point upstream of the solder bath and the inert gas is at a temperature substantially higher than the solder bath temperature.

Abstract: An automated program controlled discrete soldering system for plated holes of a printed wiring board, having a crucible for holding a discrete amount of solder and operable to travel in a substantial vertical path to a soldering position beneath the board. The solder is metered and deposited in the crucible prior to each application of laser energy to the crucible for melting the solder.

Abstract: A method of welding using a preheating insert is disclosed. The method includes the steps of positioning and igniting a combustible solid fuel mixture within a pipe to preheat the pipe by convection to a proper temperature and welding the pipe. The preferred and illustrated embodiment incorporates an encircling bottom support having a centralized hollow tube. It is made of a frangible material to be easily broken should it fall into the pipe. It supports a hollow, cylindrical, combustible heating element. The heating element is made of thermite as an example. It includes a top located deflector plate to deflect hot gases flowing upwardly from combustion against the wall of a pipe to be heated. The apparatus is concentrically located within the pipe in the vicinity of the pipe section to be heated.

Abstract: A semiconductor die surface heater and a method of using the die surface heater as a wire bonding assembly are provided. In the preferred form, the semiconductor die surface heater comprises two heaters. A preheater heats the surface of a semiconductor die which is attached to a lead frame via radiant energy. A clamp which positions both the semiconductor die and lead frame during the wire bonding has a window portion with a surface clamp heater for heating at least the portion of the clamp around the window.

Abstract: A method and apparatus is provided for attaching forging handles in the nature of studs to metal billets. The billets are passed in end-to-end relationship through a furnace following which the heated billets are individually delivered to a welding station where a welder welds a stud to the billet. The welder includes a welding head which is shifted by a translation mechanism from a feeding position where studs are successively fed to the welder to a welding position in which the stud is brought into engagement with the billet and electrical current is delivered through the stud to produce the weld.

Abstract: A continuous soldering furnace for the assembly of electronic components on a support which is opaque to infrared rays by a soldering product, includes a metal muffle, an endless metal belt, one or more heaters extending over a part of the muffle, a forced cooler extending over another part of the muffle which is situated following the preceding part, parts for introducing one or more gases inside the muffle, closures provided at each end of the muffle. The heaters are both external to the muffle and inside the muffle. The furnace is adapted for use in the electronics industry.

Abstract: A combustor liner for a gas turbine engine, which has become distorted during use or repair, is restored to its original dimensions by selective heating at two circular locations, accompanied by outward radial replacement. An induction coil is used to heat the liner. When the support ring parts are also replaced, the high temperature mechanical reforming procedure is such that the subsequent distortion which accompanies the welding replacement of support rings is compensated for.

Abstract: An improved preheater for use in mass soldering apparatus employing a bank of quartz lamp heaters mounted in parabolic reflectors and including switching means for switching the quartz heaters on and off in response to the presence of a circuit board on a conveyor passing through the preheater.

Abstract: Disclosed is a brazing filler metal composition comprising, by weight, about 3.0% to 4.0% chromium, about 1.0%-2.0% boron; about 2.0%-2.5% silicon; about 1.0%-2.0% iron; about 5.0%-6.0% phosphorus; a maximum of about 0.06% carbon and the remainder nickel. Further disclosed is a vacuum brazing process utilizing said filler metal composition.

Abstract: Disclosed is a brazing filler metal composition comprising, by weight, about 8% to 11% chromium, 2.0%-3.0% boron, 3.0%-4.5% silicon, 2.5%-4.0% iron, 7.0%-9.0% tungsten, a maximum of about 0.06% carbon and the remainder nickel. Further disclosed is a vacuum brazing process utilizing said filler metal composition.

Abstract: A method of fabricating a seal between a ceramic and an alloy comprising the steps of prefiring the alloy in an atmosphere with a very low partial pressure of oxygen, firing the assembled alloy and ceramic in air, and gradually cooling the fired assembly to avoid the formation of thermal stress in the ceramic. The method forms a bond between the alloy and the ceramic capable of withstanding the environment of a pressurized water reactor and suitable for use in an electrical conductivity sensitive liquid level transducer.

Abstract: An actuator means for a remote temperature control unit includes a base member onto which an edge of a diaphragm is crimped, a ring of solder is placed on the base member adjacent the crimped edge of the diaphragm. This assembly is placed in an oven in an inert environment with the temperature at about 575.degree.-585.degree. F. for about three hours. The temperature is then raised to 615.degree.-625.degree. F. for about twenty minutes to melt the solder to sealingly solder the diaphragm to the base member. The oven is cooled to about 250.degree. F. while it is in an inert condition and the finished assembly is removed from the oven.

Abstract: Plates of a plate heat exchanger, defining between them a space adapted to be traversed by a heat-exchange fluid, are held together and are soldered in a chamber in which the plates are heated by passing a heating fluid, generally an inert gas, directly through the passages between the plates.

Abstract: A method of joining shafts is disclosed in which a welded joint is formed between the shaft ends of, for example, a turbine and a generator inside of an assembled turbogenerator structure. A built-up weld portion is provided on the end of each shaft, which is machined to form a welding groove. During installation of the equipment, such as a turbogenerator arrangement, a welding ring is placed onto the end of one shaft. Welding powder is deposited in recesses formed between the shafts and the welding ring. The second shaft is then pressed against the welding ring. The shaft sections are preheated and the groove is supplied with welding material to join the sections while the shafts are being rotated. After completion of the weld, the seam is checked for structural integrity.

Abstract: Failure under stress of brazed aluminum assemblies prepared by fluxless brazing is prevented by controlling the grain size before brazing of the material in contact with the brazing alloy to be at least 60.mu..

Abstract: Compacted-particle sheets are wrought from essentially scrap aluminum. A relatively thick composite laminate of such sheets is then produced by preheating a plurality of compacted-particle sheets and bonding them together by hot rolling in a single pass through a hot rolling mill to achieve a thickness reduction of about 50 percent. A second pass through a rolling mill results in a further 20 percent reduction and improved bonding. Improved laminate qualities are also obtained by further laminating with other aluminum alloys and other metals.

Abstract: A rim element is at first provided with teeth and welded to an apertured disc. The resulting gear is temperhardened and subsequently assembled on a shaft or hub. The gear is welded to the shaft or hub and ground.

Abstract: A process and machine are disclosed for reflowing solder plated continuous flexible circuit webs. During reflow in a vapor environment, the flexible web is maintained in a planar orientation to produce a relatively uniform distribution of solder. Virtually all of the heat transfer fluid used in producing the vapor is recovered and retained.

Abstract: Apparatus for bonding the tubular joints of a heat exchanger using an ultrasonic soldering process in which the heat exchanger structure is heated while the joints thereof are immersed within a molten solder bath thereby preventing excessive amounts of heat from being drawn out of the joint region during the bonding process.

Abstract: The formation of voids through interdiffusion in bimetallic welded structures exposed to high operating temperatures is inhibited by utilizing an alloy of the parent materials in the junction of the parent materials or by preannealing the junction at an ultrahigh temperature. These methods are also used to reduce the concentration gradient of a hardening agent.

Abstract: A series of thin-walled, heat exchange tubes are soldered to return bends of similar materials so as to complete a flow path through the tube bundle by a process which comprises press-fitting the return bends to the tubes, preheating the return bends and portions of the tube adjacent the bends to a temperature, the average of which is approximately the soldering temperature, soaking the preheated portion in a liquid which will equalize the temperature of the various preheated portions, and ultrasonically soldering the return bends to the tubes.

Abstract: An apparatus for soldering a wire to a terminal includes a plurality of connector clamps secured to a turntable for positioning each clamped connector adjacent a hot air blower. The hot air blower blows hot air toward a solder ring and heat shrinkable tube surrounding the wire and a corresponding connector terminal for melting the solder and shrinking the tube. The apparatus includes a baffle for redirecting the blown hot air back toward the solder ring and tube assembly for preheating the assembly.