Showing papers on "Filler metal published in 1990"

Microstructure of Alumina Brazed with a Silver-Copper-Titanium Alloy

Abstract: Joints of high-purity Al2O3 were made with a 56Ag-36Cu-6Sn-2Ti (wt%) experimental alloy by vacuum brazing at 900°C for 20 min. The microstructure at the ceramic-metal interfaces was examined in cross-sectional specimens of the joints, and phases formed by reaction between the braze filler metal and the Al2O3 were analyzed for composition and crystal structure in a transmission electron microscope. A 0.1- to 0.2-μm-thick layer formed directly on the Al2O3 surface. This layer was Ti-rich, had the face-centered-cubic crystal structure with a lattice parameter of 0.423 nm, and was identified as oxygen-deficient γ-TiO. The second reaction layer was ∼3 μm thick, and it separated the TiO layer from the metallic phases of the braze filler metal. The structure of this layer, as determined by electron diffraction, was diamond cubic of the space group Fd3m, with a lattice parameter of 1.137 nm. The combination of microanalysis and diffraction data confirmed that this phase was Ti3(Cu0.76Al0.18Sn0.06)3O and indicated that it can be classified as an n phase.

Basic metal cored electrode

Abstract: A consumable welding element for arc welding comprising a steel sheath surrounding a compacted core containing metal alloying powders and an essentially 100% basic compound in an amount less than about 1.60% of the total weight of said element. The basic compound is calcium fluoride powder which is preferably in the range of about 0.1% to about 0.9% calcium fluoride powder by total weight of the element. As another feature the core of the element contains a specific agent for decreasing the amount of diffusible hydrogen in the weld metal. This new element may be a filler metal for TIG welding; however, it is preferably a consumable electrode for MIG welding.

Low hydrogen basic metal cored electrode

Abstract: A consumable welding element for arc welding comprising a steel sheath surrounding a compacted core containing metal alloying powders and an essentially 100% basic compound in an amount less than about 1.60% of the total weight of said element. The basic compound is calcium fluoride powder which is preferably in the range of about 0.1% to about 0.9% calcium fluoride powder by total weight of the element. As another feature the core of the element contains a specific agent for decreasing the amount of diffusible hydrogen in the weld metal. This new element may be a filler metal for TIG welding; however, it is preferably a consumable electrode for MIG welding.

Effects of welding flux additions on 4340 steel weld metal composition

Abstract: The effects of CaF2, CaO and FeO additions on weld metal chemistry were evaluated for the manganese — silicate flux system. Comparisons were made between AISI 4340 steel and lowcarbon steel welds to understand the weld metal chemistry. The results show that the elemental transfer from the slag to the weld metal and vice versa cannot be consistently explained using thermodynamic data; e.g., the carbon/oxygen partition is apparently controlled by a CO reaction in the 1010 steel welds, but the AISI 1020 and 4340 steel welds show constant carbon contents despite increasing oxygen levels. In addition, data are reported as a resource for future analytical and comparative purposes. Introduction Submerged arc welding of high integrity can be achieved through proper selection of the wire and flux combination for the specific base metal and welding parameters. Small amounts of alloying elements such as nickel, chromium and molybdenum are added to steels to increase strength, hardness or toughness, as is the case with AISI 4340 steel. Generally, welding low-alloy steels requires more careful control of procedures and selection of consumables than welding the carbon steels. Moreover, the oxygen potential of the flux influences the loss or gain of alloying elements during welding, the weld-deposit oxygen content, and the type, size and distribution of oxide inclusions in the solidified weld metal. The effective application of the submerged arc welding process for joining high-strength, low-alloy steels depends heavily upon understanding the behavior of the flux. Understanding the elemental P. A. BURCK and D. L. OLSON are with the Center for Welding and joining Research, Colorado School of Mines, Golden, Colo. J £ INDACOCHEA is with the University of Illinois at Chicago, Chicago, III. transfer mechanisms between the flux and the weld metal can be attained by studying the influence of each chemical additive on the flux behavior. To determine the many slag/weld metal chemical reactions occurring simultaneously during welding, a state of thermodynamic equilibrium has been assumed to be attained. The basis for this assumption is that the high temperatures and high surface-to-volume ratio associated with the welding process counteract the short time available for a reaction to be completed (Ref. 1). Chai and Eagar (Ref. 2) reported that the very short times and the large thermal gradients involved in the process prevent overall slag-metal equilibrium from being reached. They also reported that an understanding of kinetics, in combination with the thermodynamic limits of the process, would be necessary to determine the final weld metal composition. Blander and Olson (Ref. 3) also discussed the influence of kinetics, the role of interfacial reaction, and the degree to which equilibrium is approached. This paper is a part of the systematic investigation undertaken by the Colorado School of Mines (Refs. 3-7) to better understand the behavior of different flux additions to the manganese-silicate and lime-silicate flux systems. The influence of FeO, CaO and CaF2 additions to a manganese-silicate flux on AISI 4340 steel weld metal chemistry is reported here. In addiKEY W O R D S Welding Flux Effects Flux Additions 4340 Steel Weld Metal Weld Composition Submerged Arc Fluxes 1020 Steel Weld Metal Ca2/CaO/FeO Addition Mn-Silicate Fluxes SAW Flux Systems tion, a comparison of the effects of CaF2 and FeO additions to a manganese-silicate flux on welds on AIS11020 and 4340 steels was made in an effort to understand the effect of alloying elements on weld metal chemistry. The results presented in this paper should be a useful database for future analytical modeling and comparisons. Materials and Procedure Single pass, bead-on-plate welds were made using the submerged arc welding process on AIS11010,1020 and 4340 steel base plates. The dimensions of the plates were 73 X 203 X 13 mm (2.9 X 8 X 0.5 in.). The welding wires used were AWS Type E70S-3 for welds produced on AISI 1010 and 1020 steels, and Type EM12K for AISI 4340 steel welds. Compositions of the base plates and welding wires are given in Table 1. The submerged arc welding process was performed using direct current, electrode positive. The welding parameters were maintained constant at 30 V, a travel speed of 8 mm/s (19 in./min), and the wire speed was varied to give 500 A. All welds were made with a heat input of 1.9 kj /mm (48 kj/in.). Three different flux systems were used in this investigation: Si02"MnO-FeO, Si02" MnO-CaO and Si02-MnO-CaF2. The fluxes were prepared using reagent grade chemical powders. The flux compositions were reported as wt-% MnO because M n 0 2 decomposes to form MnO during the melting operation used to produce the fused flux. The iron ion in the fused flux was determined to be in the Fe + state and is reported as wt-% FeO (Ref. 10). The reagent-grade powders were weighed and mixed prior to induction melting. The powders were then placed in a graphite crucible for the melting operation. All fluxes were brought to 1773 K. The crucible was then removed from the furnace and the flux poured onto a stainless steel plate to solidify. After cooling, the fused fluxes were crushed and sized. Fluxes sized 14 to 100 mesh were used for WELDING RESEARCH SUPPLEMENT 1115-s

Computerized radiographic sensing and control of an arc welding process

Abstract: This paper summarizes an effort in which real-time radiography was implemented for on-line arc welding process study and control. X-ray penetrating radiation was used for volume observation in the welding pool and the heat-affected zone during the weld process. The advantages of such a technique are online detection and monitoring of defect formation in the weld and capability to study metal fusion and filler metal/base metal interaction and metal transfer in the welding pool. This technique may also be used for postservice, real-time remote testing of weld quality.

Joining of Si3N4 using Ag57Cu38Ti5 brazing filler metal

Abstract: Hot-pressed Si3N4 was joined using Ag57Cu38Ti5 brazing filler metal at 1103 to 1253 K for 5 min in a vacuum. The interface reactions between Si3N4 and the brazing filler metal during brazing are reported. An important event is sufficient interface reaction, characterized by the formation of a layer of TiN with an appropriate thickness at the ceramic-filler interface. The joining strength of the butt joint depends on the interface reaction, and a maximum joining strength of 490 MPa measured by the four-point-bend method is achieved for the Si3N4-Si3N4 joint brazed at 1153 K for 5 min. It is also discussed how to design the best brazing filler metal for joining ceramic to ceramic or ceramic to metal.

Heat resisting structure

Abstract: An improved heat resisting structure for treating the exhaust gas of a gas engine is disclosed. The heat resisting structure has a honeycomb-form structure formed of corrugated and flat sheets which are alternately overlapped, rolled up, and joined via a brazing filler metal to make a roll-form structure. The brazing filler metal is made of iron(Fe)-base brazing filler metal, and the stainless steel corrugated sheet and flat sheet constituting the base metal are similar in composition. Accordingly, almost no difference exists in the coefficient of thermal expansion between the brazing filler metal and the base metal. As a result, cracks caused by thermal stress between them due to a difference in coefficient of thermal expansion is avoided even when used repeatedly.

Laser beam welding method

Abstract: PURPOSE:To perform sound laser beam welding at high speed on thick-wall resins by using filler metal with high absorptivity of a laser beam which does not affect adversely joint performance of a joining part of the same material, etc., with high absorptivity for the joining part. CONSTITUTION:A lower material (sheet) 2 to be joined is set on a base plate and the filler metal (colored sheet) 3 which is colored material of the same quality as the upper and lower materials (sheets) 1 and 2 to be joined and has high absorptivity of the laser beam is placed thereon. A convergent laser beam 4 is projected and absorbed via a condenser lens 5 on a joining line of the upper material (sheet) 1 to be joined and heat generation and fusion are proceeded with the filler metal (colored sheet) 3 as a main point. Consequently, the filler metal (colored sheet) 3 of the upper and lower materials (sheets) 1 and 2 to be joined and the adjacent vicinity are molten partially and proceeded to joining via the cooling process.

Effect of electrochemical reactions on submerged arc weld metal compositions

Abstract: The purpose of this work is to investigate the relative influence of electrochemical and thermochemical reactions on the weld metal chemistry in a direct current submerged arc welding process. Chemical analyses were carried out on the melted electrode tips, the detached droplets and the weld metal for both electrode-positive (reverse) polarity where the welding wire is anodic and electrode-negative (straight) polarity where the welding wire is cathodic

Brazed ceramic-metal composite

Abstract: A composite consists of a ceramic brazed to another ceramic by means of a joint layer therebetween. The joint layer comprises a porous metal interlayer and an active brazing filler metal penetrating through the porous metal interlayer.

Effect of Additional Elements in Ag-Cu Based Filler Metal on Brazing of Aluminum Nitride to Metals

Abstract: Brazing of aluminum nitride to copper was performed using Ag-Cu-Ti, Ag-Cu-Ti-Co and Ag-Cu-Ti-Nb brazing filler metals in an argon atmosphere. The reaction layer formed at the interface between AlN and braze layer in AlN-Cu joints was found to increase by increasing brazing time for all brazing filler metals used. In the case of the fillen metal Ag-Cu-Ti-Nb, a thinner reaction layer was formed in comparison with the cases of using other filler metals. Form an EPMA analysis, it was found that not only Ti, but also Nb were concentrated in this thin reaction layer. From XRD analysis, it was found that TiN lattice was distorted by Nb addition. Shear strengths were measured for AlN-W joints at room temperature. The joint brazed at 1 173 K for 0.3 ks using Ag-Cu-Ti filler metal showed a strength of 118 MPa. In the case of using Ag-Cu-Ti-Co filler metal, almost the same shear strength, 116 MPa, was obtained after brazing at 1 173 K for 0.6 ks. The joints brazed at 1 173 K for 0.3 ks using Ag-Cu-Ti-Nb filler metal exhibited the maximum shear strength 147 MPa. The shear strength of the joints was discussed in relation to the thickness of the reaction layer.

TIG and Plasma Welding: Process Techniques, Recommended Practices and Applications

Abstract: Process fundamentals Applying the TIG process Mechanised Orbital tube welding Tube to template welding Micro-TIG welding Hot wire TIG welding Narrow gap TIG welding Process fundamentals: Applying the plasma process The future.

Wet welding electrode evaluation for ship repair

Abstract: An evaluation of submerged arc welding (SMAW) electrodes shows that wet welding is a viable process for underwater repair and maintenance of ships.

Filler metal for surface reforming of aluminum material

Abstract: PURPOSE: To form a surface reformed layer having excellent wear resistance on an aluminum material by using an aluminum alloy filler metal contg. prescribed ratios of Si, Cu and Ni and build-up welding this filler metal to the desired section of an aluminum base metal. CONSTITUTION: The filler metal for surface reforming of the aluminum consisting of 1 to 30w.% Si, 1 to 30wt.% Cu and 1 to 5wt.% Ni and consisting of the balance aluminum and unavoidable impurities is welded to the surface of the aluminum material to form the surface reformed layer. The surface reformed layer having excellent wear resistance and adhesive property is formed, by which the application range of the aluminum material to wear resistant parts is widened. COPYRIGHT: (C)1992,JPO&Japio

Non-consumable electrode arc welding control method

Abstract: PROBLEM TO BE SOLVED: To provide a non-consumable electrode arc welding control method performed while feeding filler wire, in which the insertion height of the filler wire can be always maintained to prescribed value even if torch height control of fixedly retaining arc length is performed. SOLUTION: In the no-consumable electrode arc welding control method in which torch height control is performed for suppressing the change of arc length La accompanying a non-consumable electrode 1 during welding, and welding is performed while feeding filler wire 5 through the inside of a wire guide 52 fitted to a torch 4 via a fitting member 51, the fitting member 51 is elevation-controlled to the longitudinal axial direction of the torch 4 in such a manner that the insertion height Lh of the filler wire 5 to an arc generation part is made certain. In this way, the change of the insertion height of the filler wire 5 accompanying the control of arc length can be suppressed, and satisfactory welding quality can be obtained. COPYRIGHT: (C)2011,JPO&INPIT

Carbide Addition on Aluminum Alloy Surface by Plasma Transferred Arc Welding Process(Surface Processing)

Abstract: Effect of carbide addition on the surface characteristics of aluminum alloy 5083 has been investigated with the plasma transferred arc welding process (DCSP) of NbC, TiC or SiC powder. Optimum overlaying conditions under which bead appearance is superior and porosities in overlaid metal are lesser are determined. Moreover some characteristics of overlaid metal containing carbide are evaluated under these optimum conditions. The results are summarized as follows: (1) The maximum area fraction of carbide in overlaid metal is about 40% for NbC and TiC, and about 30% for SiC, (2) Vickers hardness of overlaid metal containing carbide is in the range between 111 and 141hgf/mm2, (3) Abrasive resistance of overlaid metal at higher sliding speed is remarkably improved by the addition of carbide although that at lower sliding speed is not almost improved, (4) In the 180 degree bend test, cracks appear not in the boundary layer between overlaid and base metals but only in overlaid zone, meaning that the boundary layer is sound enough for ductility.

Heat exchanger for hot-water supply

Abstract: PURPOSE: To obtain the heat exchanger which is excellent in low temperature corrosion resistance and to prevent the fin from being closed up by a corrosion product by brazing and joining a tube made of iron and a fin made of Al at a specific temperature through a specific brazing filler metal. CONSTITUTION: A tube 1 made of iron and a fin 2 made of Al are brazed and joined at a temperature of ≤570°C through an Al - Si - high Zn compound brazing filler metal 24. In such a way, heat exchanger for hot-water supply in which an intermetallic compound layer of brittle FeAl 3 , etc., is not generated in the joint interface, or it is suppressed is obtained. Also, by covering the tube 1 with an Ni or Cr layer 7 in advance, generation of the intermetallic compound layer is further suppressed. COPYRIGHT: (C)1991,JPO&Japio

Brazing filler metal

Abstract: PURPOSE:To allow brazing of a low m. p. without the contamination of the inside wall of a joining furnace, the contamination of the joined material and the exertion of adverse influence on the human body by constituting the brazing filler metal of substantially Ag and Cu and at least >=1 kinds of the other elements which form eutectic crystal with the Ag and Cu and satisfy specific conditions. CONSTITUTION:One or more kinds of the other elements which satisfy at least one of the conditions (a) to (d) to the Cu and satisfy at least one of the conditions (e) to (h) to the Ag are added to the Ag and the Cu. Although there may be a case in which a compd. is contained between the Ag and the Cu and these additive elements, the possession of the eutectic point of >=3 elements or the m. p. approximate to this point is possible. The brazing filler metal having <=730 deg.C m. p. is obtd. in this way and the brazing at the working temp. below 750 deg.C is possible by adding the 3rd elements to the Ag and the Cu. The joint strength thereof compares favorably with the joint strength of an Ag-Cu eutectic alloy.

Micro-additions to tin alloys

Abstract: Tin-based alloys that include micro-additions of certain elements avoid the discoloration that otherwise afflict those alloys when they are melted. The discoloration, which results from tin oxidation, correlates with poor performance of the alloys in filler metal applications. A preferred method of preparing the alloys of the invention is by rapid solidification from the melt.

Coupling method for hemming joined part

Abstract: PURPOSE:To eliminate the need of applying a sealing material, and also, to improve the rigidity of a panel by inserting and holding a brazing filler metal between panels of a part in which a cross sectional shape is varied three- dimentionally in a joined part and executing the forming, and welding the overall length of the joined part by a laser CONSTITUTION:In a hemming joined part 7, press forming is executed by inserting and holding a brazing filler metal 8 between a turn-back part 5 of an outer panel in a part in which a cross sectional shape of a corner part 1a, etc, of a door 1 is varied three-dimensionally, and a terminal part 6 of an inner panel 4 Subsequently, the hemming joint part 7 is brought to laser welding 9 extending over the overall length As for the hemming joint part 7, a general part is coupled by laser welding 9, the corner part 1a of the door 1a of the door 1 is melted by the brazing filler metal 8, and thereafter, the hemming joined part 7 is coupled by the solidified brazing filler metal 8a and laser welding 9 In such a way, the watertightness is secured enough, and it becomes unnecessary to apply a sealing material made of a resin

Phosphorous copper based alloy with tin and antimony

Abstract: A phosphorous copper based alloy having combined tin and antimony contents up to approximately six percent each for brazing filler metal joining copper and copper alloys producing strong clean joints at lower brazing temperatures Silver added in amounts of 1-18% offers the ability to lower brazing temperatures further

Contact tip for arc welding

Abstract: A contact tip for arc welding includes a feed surface constructed of conductive material which has a negative thermoelectromotive force with respect to pure platinum at temperatures above 0° C. When welding current flows from the contact tip to a welding wire, an endothermic reaction occurs at the feed surface to lower the temperature of the feed surface and to improve the thermal durability of the contact tip.

Process for welding coated thin sheets, especially zinc coated sheets

Abstract: A process is disclosed for welding coated thin sheets, especially zinc-coated sheets. Carrying out the welding with the plasma arc welding process in which, in addition to argon as centre gas, an argon/oxygen mixture containing 87 to 97% by volume of argon and 3 to 13% by volume of oxygen is used as outer or protective gas yields, surprisingly, a very good welding result, and consequently this process is an alternative to the known MAG fusion welding process.

High strength aluminum brazing sheet

Abstract: PURPOSE: To improve the strength and corrosion resistance of a brazing sheet and to reduce the diffusion of a brazing filler metal by specifying the compsn. of an Al allay core material and the density of intermetallic compounds having specified grain size. CONSTITUTION: In this Al brazing sheet, an Al allay constituted of, by weight, 0.05 to 0.80% Si, 0.05 to 0.6% Fe, 0.1 to 1.0% Cu, 0.6 to 1.6% Mn, 0.05 to 0.5% Mg and the balance Al and contg. intermetallic compounds having 0.02 to 0.2μ grain size by 20 to 2000 pieces/μ 2 in number density is used as a core material. Then, it is constituted in such a manner that the face on the side in contact with a refrigerant of the core material is clad with an Al alloy electrochemically baser than the core material and the other face is clad with an Al-Si series alloy. Si promotes the precipitation of Mn, increases intermetallic compounds, improves its strength and has age hardening after brazing together with Mg. Fe forms intermetallic compounds together with Mn to improve its strength, Cu improves its strength and corrosion resistance and Mn is essential for distributing intermetallic compounds into the alloy. The number density of the intermetallic compounds improves its strength, reduces the diffusion of a brazing filler metal and improves its corrosion resistance. COPYRIGHT: (C)1992,JPO&Japio

Joining method for iron compound sintered parts by brazing

Abstract: PURPOSE:To manufacture parts by brazing by using green compact as a sintered member and a brazing filler metal, and also, constituting the brazing filler metal of a composition which is mainly composed of Cu-Ni-Mn compound powder and obtained by adding at least one kind of powder of Fe, Cu, Sn, etc., at the time of joining an iron compound sintered member by brazing. CONSTITUTION:At the time of brazing and joining each iron compound sintered member or the iron compound sintered member and a steel material, as for the iron compound sintered members 1, 2, a dust formed body by iron powder is used, and also, as for a brazing filler metal 3, green compact obtained by mixing at least one kind of 3-15% iron powder, 1-10% Cu powder and 1-7% Sn powder into alloy powder whose composition is Cu+(30-50%)Ni+(15-25%)Mn+(1-5%)Si+(0.5-2.0%)B is used, and the brazing filler metal 3 is interposed between the members to be brazed 1, 2 and they are assembled to a desired shape, and thereafter, heated to a temperature exceeding a melting temperature of the brazing filler metal and the iron compound green compact 1, 2 is sintered, and also, the brazing filler metal which has been melted is infiltrated (b) deeply into the material to be brazed, and also, an expanse in the (a) direction of a joint surface is enlarged, and the iron compound sintered member of a complicated shape by brazing and parts by a steel material can be manufactured simply.

Brazing alloy for aluminum and brazing sheet for heat exchanger made of aluminum

Abstract: PURPOSE:To improve the corrosion resistance of the heat exchanger made of Al by using a brazing alloy contg. Si, Fe and Ti respectively at specific ratios and consisting of the balance Al and cladding the alloy to a core material which is electrochemically nobler than this alloy. CONSTITUTION:The brazing alloy for Al contg., by weight, 5-13% Si, 0.05-1.0% Fe and 0.06-0.3% Ti, and the balance Al and unavoidable impurities is prepd. The brazing alloy is then clad to both surfaces or one surface of the alloy core material contg. 0.5-1.5% Mn, 0.3-1.0% Cu, 0.1-0.7% Fe, 0.03-0.4% Si, and contg. 1 or 2 kinds of either of 0.05-0.3% Cr and 0.05-0.3% Zr at need to form the brazing sheet for the heat exchanger. The brazing filler metal is converted to the metal which is electrochemically base to the core material in this way so that the brazing filler metal plays the role of a sacrificial anode on the core material. The corrosion resistance of the heat exchanger is, therefore, improved.