Showing papers on "Cold welding published in 1985"

Feasibility Study of the Welding of Sic

Abstract: In a brief study of the feasibility of welding sintered alpha-SiC, solid-state welding and brazing were investigated Joint quality was determined solely by microstructural examination Hot-pressure welding was shown to be feasible at 1950 C Diffusion welding and brazing were also successful under hot isostatic pressure at 1950 C when boride, carbide, and silicide interlayers were used Furnace brazing was accomplished at 1750 C when a TiSi2 interlayer was introduced

Method and apparatus for welding thin metal sheets

Abstract: There is described a method for welding thin metal sheets (A, B) by the localized heating of limited juxtaposed zones of the metal sheets to be welded to cause their fusion and to form spot welds (S). In each weld zone, the metal sheets (A, B) are heated and fused along a closed line so that each weld spot (S) has a substantially annular configuration in cross section in a plane parallel to the metal sheets. This welding may be achieved for example with the use of a laser (2) produced by a laser source (1), or by electrical resistance welding with a pair of opposed electrodes (6, 7) the ends whereof which are intended to grip the metal sheets (A, B) are suitably shaped.

DTA and TGA Studies of Four Ag-MeO Electrical Contact Materials

Abstract: The results of the differential thermal analysis (DTAt and the thermal gravimetric analysis (TGA) of four different metal oxides and their respective Ag-MeO materials indicated that the thermochemical properties of the Ag-MeO materials are directly influenced by the metal oxide components. The energies required to bring the different Ag-MeO materials into different thermal states were calculated, diseussed, and compared. This investigation postulates two hypotheses. First, the arc erosion loss of a contact material depends on the erosion mode. If the predominate mode is splattering, then the Ag-CdO material may be the superior to pure silver because it requires more heat to reach an equivalent thermal state. Second, the oxide, the function of which is to weaken the contact welding, tends to remain on the surface thus increasing the contact resistance. Cadmium, due to its low boiling point, evaporates from the surface. These unique properties may account for the superiority of Ag-CdO as a contact material over other single oxides.

The Application of Diffusion Welding to Aircraft Titanium Alloys

Abstract: Diffusion welding is one of the most promising fabrication methods in the aircraft industry. It realizes the complex, hollow and near-net shape structures from stock plates instead of forging materials, and the metallurgical properties of the base metals can be fully preserved in the diffusion welded joints.Until now we have carried out research on the diffusion welding of aircraft titanium alloys and put it into practical use as a production technique.This paper describes the results of the current application study on diffusion welding of titanium alloys for aircraft parts.

Study on surface film on diffusion welded interface (Report 1) - Auger microanalysis of surface film on diffusion welded interface.

Abstract: The surface film of weld parts is a very important factor affecting the weld characteristics of diffusion welds. It is desirable to clarify the behavior of the surface film on the diffusion welded interface. In this study, the surfaces before and after diffusion welding were observed with Auger electron spectroscopy. Composition and thickness of the welding surface, and the relation between change of surface composition by diffusion welding and tensile strength of welded joints are investigated. The following results were obtained.1) The films of the welding surface of aluminum, copper, iron and SUS 304 stainless steel are composed of oxygen, carbon and base metal.2) Composition and thickness of the surface films of various materials do not so much depend on the surface treatment such as the degreasing with acetone and the annealing in a vacuum.3) The surface film along the welded interface of aluminum does not change during diffusion welding, but those of copper, iron and SUS 304 stainless steel disappear.4) When the surface film disappears during diffusion welding, metallic bonding is formed at intimate contact area along the welded interface. The stability of the surface film has an influence on tensile strength of welded joints.5) The segregation of sulfur is observed on no-contact surface along the welded interfaces of copper, iron and SUS 304 stainless steel, but it does not have much effect on tensile strength of welded joints.

Recent Advance in Ultrasonic Welding of Metal and Plastics

Abstract: New ultrasonic metal and plastic welding methods with multiple vibration systems and various complex modes of same and different vibration frequency have been proposed and studied as follows ; (1) ultrasonic spot welding of metal with two vibration systems for joining thick specimens. (2) ultrasonic welding of ring shape weldment with two vibration systems (3) ultrasonic butt welding for joining of thick metal specimens end to end. (4) ultrasonic plastic welding with two vibration systems -- (A) direct welding for joining specimens with small damage and with small power. (B) transmission welding for joining thick and large welding specimens by controlling of vibration phase difference. (5) ultrasonic plastic welding with welding tip pair -- (A) welding tips vibrating vertical to welding surface, and (B) vibrating parallel to welding surfaces for joining of lapped sheet or thin plate welding specimens with the very small width. effective for joining of metal and plastics successfully.

Joining method for copper wire and ferrous component

Abstract: PURPOSE: To join the both stably with the solid phase pressure welding of the base metal each other without using a solder specially nor any damage to the apparatus due to the solder ball by performing a resistance welding by pinching the copper wire which is plated by the alloy of low melting point and ferrous component between electrodes. CONSTITUTION: The solder plated lead copper wire 2a on the tin plated iron bolt terminal 3a is placed on the copper plated in-tank type electrical fuel pump for automobile, for instance, and is subjected to a resistance welding by being pinched between electrodes. In this case, the solder only is melted by the resistance heating and moved to the periphery from the center part of the pressure welding. On the pressure welding center part a clean neoface is faced and a strong metallic combination is formed in the form of a solid phase pressure welding with the action of the interationic attraction force. The solder as the sub-material is almost disused, there is no induction of the apparatus damage due to the solder ball, the automation is made possible and a stable combination is performed. COPYRIGHT: (C)1987,JPO&Japio

Application of Laser Beam Welding to Thin Steel Sheet

Abstract: As Laser beam can be focused to pointed area, it is suitable to apply high speed welding of thin sheet metal. This experiment was carried out to know what advantage can be expected by applying Laser beam welding to surface coated steel sheet and austenitic stainless steel.The results obtained in this report are as follows;1) Steel sheet can be welded with much smaller distortion by Laser beam welding, compared with TIG welding. For coated sheet, Laser beam welding gives less damage to coated layer than that of TIG weld-ing. It is possible to make full penetration weld to use 3-5 times faster speed by Laser beam welding than by TIG welding.2) TIG weld metal of Zn coated sheet shows Zn rich region at surface but Laser weld metal does not.3) Laser beam welded joints of stainless steel show little weld decay tendency, which is almost same level as electron beam welded joint.

Method of automatic resistance welding of electric contact plates onto a supporting belt and semifinished products for the fabrication of contacts of hard and brittle contact material to be welded onto a supporting belt.

Abstract: Methods for the automatic resistance welding of metal plates forming electric contacts to predetermined locations and semifinished products for the fabrication of contacts welded on a backing strip are known. A method for the automatic resistance welding of contact plates of a hard and brittle contact material, such as molybdenum and in particular tungsten, is specified in which a solder layer is applied to the welding side of a contact-material strip or bar of molybdenum or tungsten and in which, at the spacing between the contact dimensions, slits are made on the contact-material surface remote from the welding side, the contact plates being detached at these slit-like separating points. A corresponding semifinished product is a contact- material strip or bar of molybdenum or in particular tungsten or their base alloys which has a solder layer on the side to be welded on.

Cladding material of iron or steel base alloy and copper alloy material

Abstract: PURPOSE:To provide a titled clad material which has high joining power, is highly resistant to corrosion against sea water and ammonia atmosphere and has good wear resistance and workability by joining a copper alloy material having the specific compsn. consisting of Be, Sn, Ni and Cu to an iron or steel base metal and expanding the same. CONSTITUTION:A copper alloy material consisting of 0.01-2.0wt% Be, 1.0-9,0% Sn, 1.0-30.0% Ni and the balance Cu is joined to an iron or steel base metal by explosive welding, hot welding, cold welding, etc. and is then expanded by rolling, by which a thin clad material is easily obtd. without peeling of each material. If the component compsn. of the above-mentioned copper alloy is below the lower limit, the joining performance is decreased and if the upper limit is exceeded, the hardness increases too much. The formation of the clad metal is not feasible in either case. The resultant clad material is age-hardened preferably at about 300-500 deg.C, by which the mechanical strength and the corrosion resistance against ammonia atmosphere are improved.

Process for socket-joining thermoplastics-covered heating pipes using a welding mirror.

Abstract: The invention relates to a process for producing a sleeve joint of plastic-coated pipelines, especially for remote heating, two PE half- pipe shells of the same diameter, wall thickness and tolerance as the PE coated pipe are welded to one another and to the coated pipes using hot-element butt-welding. This is possible since the dimensional conformity is ensured by the half shells of the welding machine and the bevel running in the same direction at an angle of 60 DEG allows the seam pressure to be applied that is required for welding. The seam pressure is one of the welding parameters which is specified for hot- element butt-welding and is applied to both the workpieces.