Showing papers on "Cold welding published in 1979"

Joining III: Diffusion Bonding

Abstract: Diffusion bonding is another process available to the designer for the joining of beryllium. With this process, joining of clean, closely fitting parts is obtained by the application of heat and pressure. The coalescence of the base metal is achieved through atomic transport and mechanical processes at the bonding interface. Diffusion bonding has also been identified in the literature as cold welding, solid state bonding, hot pressure bonding, deformation bonding, solid state pressure welding, gas pressure bonding, and other descriptive headings.(1–8)

Universal compression fitting for pipes - uses selective clamping seals of gasket type or cold welding rings biting into pipe

Abstract: The universal pipe fitting has the ends of the pipes to be joined cut with a butt joint and located in a mounting flange. A special gasket is clamped between the pipe and the flange, with the design of the gasket depending on the type of pipe used. The gaskets comprise a small component with the major component common to all joints. For plastic pipes a flexible O ring is used and for metal pipes a cold welding ring which bites intot he pipe.

Nickel foil to aluminium component connection - uses combined ultrasonic and resistance welding

Abstract: The aluminium component is a sheet metal cathode element for an electron tube, and the nickel foil forms the connecting tag for this element which has to be secured to its contacting point by thermal treatment. The connection of the foil and the element is carried out by resistance-ultrasonic welding. The metal parts to be welded are preheated prior to welding by a voltage between 2 to 4 V and a pulsed current of 150-500 A. During welding the sonotrode pressure force is limited to 100 N/sq. mm.

Electron-Beam Technology in Switch Contacts

Abstract: The original concept was to develop a composite strip of material for switch contacts, such that the silver portion is suitably bonded to the base metal such as copper, phosphor bronze, or beryllium copper. The requirements were a metallurgically sound reproducible-nonporous uniform ductile bond. Electron-beam welding technology meets these requirements for joining switch contact materials. Fine silver, coin silver, silver cadmium oxide, and other wrought contact materials can be continuously electron-beam welded to the base metal switchblade member and then subsequently stamped and formed to the necessary switch configuration. This manufacturing technique is an improvement over the alternate joining methods of resistance welding, brazing, tungsten inert gas welding, thermocompression bonding, and the more recent laser welding.

Welding method for repairing low alloy steel

Abstract: PURPOSE: To lower residual stress by using a low alloy welding electrode of hardness lower than that of base metals as padding metal for the surface layer in contact with corrosive environments. CONSTITUTION: In the case of locally shaping off the defect part of a structure of low alloy steels, particularly Mn-Mo or Mn-Ni-Mo steels and repair-welding the same, 1W2 layers of the surface side in contact with corrosive environments are left and said part is welded with a welding electrode of the same component system as that of the base metals. Thence, the outside circumferential part around the repairing part is beforehand welded with a high-nickel-welding electrode, after which it is successively build-up welded toward the central part side by a nickel welding electrode or a stainless steel welding electrode. In this welding process, the hardened layer near the welding heat affected zone bond of the base metals is made into fine tempered martensite structure; in addition, plastic working is applied to the build-up welded metal near the welding boundary after the end of the welding, whereby residual stress is lowered. COPYRIGHT: (C)1981,JPO&Japio

Apparatus for electron beam welding

Abstract: A method and apparatus for electron-beam welding in which the electron beam is directed from an electron gun onto the material being welded through a magnetic shielding tube. the lower end of which is water cooled. In order to clear the end of the shielding tube of deposits of metal vapour and sputterings emitted from the weld cleaning devices are provided which are driven by a motor through a reduction gear, to open and close across the lowermost surface of the tube thereby cutting off or dislodging the deposits during the course of welding, that is, without interrupting the welding operation.

Annular plate exchanging method for cylinderrshaped flat bottom tank

Abstract: PURPOSE:To shorten the term of works and save the cost of construction in exchanging works by applying an external force in the radial direction to side plates, permitting deformation, and exposing the part impossible to be welded due to the interference of the side plates of annular plates and permitting simple welding. CONSTITUTION:The contact welding part between the annular plate 2a and the side plate 1 in the part A to be exchanged is cut, and the old annular plate 2a is taken out in the horizontal direction and removed. At the position of removal of the old annular plate, a new annular plate 2A having the same form and size is inserted. By the application of an external force P in the radial direction to the side plate part by means of a proper pressing device, the lower side part of the side plate 1 at which the welding line of annular plates is positioned is bent and deformed outward with the amount S of dissplacement in elastic limit. Then, the part a which is just under the side plate 1 and impossible to be welded is exposed, so the welding of this part and the inspection of said welded part are made possible.

Edge-sealing two superposed plastics films together - and severing along the resulting seams, using smooth welding tool and contoured counter-tool

Abstract: Welding has superposed plastics films together along a welding contour of any configuration and/or application of an embossment relief, e.g. a (cursive) inscription, comprises conveying the films to be welded, upon a heat-resistant (e.g. polyamide) belt and introducing the heat necessary for heating the weld seam to melting temp., using a continuously heated welding tool having a smooth surface, through a separating band into the material to be welded. During the welding step, the material being welded bears upon a cold or slightly heated counter-tool whose configuration corresponds to that of the intended welding contour. Mechanical and thermal stresses exerted upon the separating band are relatively low so that it need not be replaced very often. Cutting electrodes which allow severing of the welded films very close to the resulting seam can be used.

Seam welding method and apparatus

Abstract: A high speed seam welding system wherein single phase alternating current welding pulses are applied to electrode mechanism during only a less than maximum amplitude fractional portion of the wave form representing each successive current half cycle, and the current is substantially cut off between current applications to permit cooling. The relative seam welding movement of the electrode mechanism and the material to be seam welded is coordinated with the duration of the welding and cooling periods to more rapidly form a line of uniform weld nuggets. The system may also be operated at more conventional welding speeds to weld relatively heavy gauge materials.

Diffusion Effects of the Heat Treatment of Au-Ag on Fe-Ni Dry-Sealed Reeds

Abstract: Outward diffusion of Fe, Ni, and, Mn, and inward diffusion of Au, are two significant effects of the heat treatment of drysealed reeds consisting of Au-Ag plated on an Fe-Ni alloy with Mn added for fabrication characteristics. Diffusion coefficients and activation energies for the outward diffusion of Mn and the inward diffusion of Au are evaluated. Probable reasons for the failure modes of cold welding and high contact resistance are suggested.