Showing papers on "Filler metal published in 1988"

Welding parameters and the grain structure of weld metal — A thermodynamic consideration

Abstract: The grain structure of the weld metal can significantly affect its resistance to solidification cracking during welding and its mechanical properties after welding. An experimental study was conducted to investigate the effect of two basic welding parameters,i.e., the heat input and the welding speed, on the grain structure of aluminum-alloy welds. Gas-tungsten arc welding was performed under various heat inputs and welding speeds, with thermal measurements in the weld pool being carried out during welding and the amounts and nuclei of equiaxed grains in the resultant welds being examined using optical and electron microscopy. The experimentally measuredG/R ratios and the clearly revealed heterogeneous nuclei together demonstrated the thermodynamic effect of the heat input and welding speed on the weld metal grain structure.

Intermetallic compounds formed during brazing of titanium with aluminium filler metals

Abstract: The effect of aluminium filler metal composition on the formation of AI-Ti intermetallic compounds was investigated in brazed aluminium-to-titanium (Al/Ti) joints and titanium-totitanium (Ti/Ti) joints. The clearance filling ability was also studied. In Ti/Ti joints, the thickness of the intermetallic compound layer was strongly dependent on the aluminium filler metal composition, whereas the clearance filling ability was independent of the composition. The maximum intermetallic compound layer thickness was observed in 99.99% highly pure aluminium filler metal; therefore all additional elements reduced the layer thickness. Above all, the addition of 0.8% Si greatly reduced the thickness. After brazing at 680° C for 3 min, the intermetallic compound formed by Al-0 to 0.8% Si filler metal was found to be of type Al3Ti. Other compounds, of types Ti9Al23 and Ti7Al5Si12, were also found in joints brazed by Al-3 to 10% Si filler metals. AI-0.8% Si filler metals maintained a higher joint strength than pure aluminium filler metal under brazing conditions of high temperature and long heating time. In Al/Ti joints, AI-Cu-Sn and AI-Cu-Ag filler metal mainly formed Al3Ti, and Al-10Si-Mg filler metal mainly formed Ti7Al5Si12 at the brazed interface of the titanium side after brazing at 600 to 620° C.

High strength composite component and method of fabrication

Abstract: A composite component suitable for high temperature applications which includes a composite compact that is thermally stable at temperatures up to 1200° C., the composite compact including a thin layer of metal bonded directly to a polycrystalline table in a HP/HT press, and a metallic substrate joined to the thin layer of metal by a high strength braze joint. The method of fabrication includes the steps of: placing a high temperature braze filler metal on the upper surface of the substrate and in contact with the thin layer of metal; applying heat through the table to melt the filler metal and accomplish the high strength joint between the substrate and the thin layer of metal; and cooling the substrate by conducting heat from all but the upper surface thereof.

Tig or mig arc augmented laser welding of thick mild steel plate

Abstract: Effects of various operating parameters on penetration depth were investigated in laser +TIG and laser +MIG welding of steel plate. In laser +TIG welding (of C-Mn-Nb-V steel), DCEN TIG welding at 100-300A was closely followed by laser welding with 1-5kW beam power. Effects of welding speed, distance between TIG electrode and laser beam, focal position of laser and TIG welding current were determined. In laser +MIG welding (of C-Mn-Ni-Mo steel), DCEP helium-MIG welding at 400A was followed by laser welding at up to 5kW. Effects of arc-beam distance, focal position, joint preparation and laser beam power were determined.

Air-tight ceramic container

Abstract: A method of manufacturing an air-tight ceramic container is disclosed. This method includes the steps of coating an active metal consisting of Ti and/or Zr on an opening end face of a ceramic tubular member (1) in an amount of 0.1 to 10 mg/cm², thereby forming an active metal layer, placing a brazing filler metal on the active metal layer, placing a metal cover member (2) for shielding an opening portion of the ceramic tubular member (1) so that a peripheral portion end face of the metal cover member (1) is in contact with the brazing filler metal, and melting the brazing filler metal by heating, thereby brazing the metal cover member to the opening end face of the ceramic tubular member (1).

Resistance welding of galvanized steel

Abstract: A coating for improved resistance welding of galvanized steel parts or sheets comprises a binder, and a metal phosphide pigment, preferably a ferrophosphorus pigment, having a particle size of from about 0.1 to about 30 microns. The pigment can also include up to about 40% by weight of an additional metal such as tin, aluminum or lead, which can be combined with the metal phosphide in pigment form or deposited onto the surface of the particles. The coating can be applied to either the faying or non-faying surfaces of the galvanized steel, or to the resistance welding electrode, and may be removed, if desired, after the welding operation. The advantages of the present invention include a significant reduction in welding current and an increase in the weldability lobe width, a restoration of the dynamic resistance beta peak, and an increase in electrode life.

Flux for brazing aluminum material

Abstract: PURPOSE:To improve the strength and durability of an Al material product by constituting a flux for brazing of specific weight % potassium hydrogenfluoride and prescribed weight % of sodium fluoride CONSTITUTION:The flux for brazing Al materials is formed of the compsn which is formed by mixing 10-30wt% potassium hydrogenfluoride and 90-70wt% sodium fluoride so as to make the entire part 100wt% Such flux is charged into water and is further stirred to prepare a liquid suspension The liquid suspension is coated to the butt part of two sheets of Al sheet materials 1, 2 and is heated at a prescribed temp in a heating furnace of a gaseous nitrogen atmosphere, etc, by which the materials 1, 2 are brazed The contact part of the materials 1, 2 is wetted with the brazing filler metal over the entire length by using the flux made of such component compsn; therefore, the strength of the brazed part is improved Since the flux does not form the residues having corrosiveness, the strength and durability of the Al product are improved

Gold-palladium-nickel-copper-manganese filler metal for joining superalloy

Abstract: A filler metal for brazing parts made of superalloys has a brazing temperature of 1025°-1080° C., a solidus temperature above 1000° C., a liquidus temperature above 1018° C. and a composition of, in weight percent, 5-30 gold, 15-35 palladium, 10-30 nickel, 20-48 copper, 5-25 manganese.

Gold alloy filler metal for brazing

Abstract: PURPOSE:To obtain an Au alloy filler metal for brazing suppressing the surface roughening of the filler metal after brazing and also suppressing the occurrence of ruggedness, by incorporating a specified amt. of a specified component into an Au-Cu-Ni alloy. CONSTITUTION:This Au alloy filler metal for brazing is an alloy consisting of 10-70wt.% Cu, 1-8wt.% Ni, 0.001-1.5wt.% at least one among Ti, Zr, V and Nb and the balance Au. Since the surface roughening of the filler metal after brazing is suppressed and the occurrence of ruggedness is also suppressed, even when a member brazed with the filler metal is subjected to acid cleaning or plating, only a small amt. of a cleaning soln. or the like enters the surface recesses in the filler metal and the tarnish and corrosion of the brazed part are inhibited.

Manufacture of aluminum brazing sheet

Abstract: PURPOSE: To improve the brazability and corrosion resistance of the title sheet by cladding a core material of an Al-Mn-Cu alloy subjected to homogenizing treatment at a prescribed temp. with an Al brazing filler metal and subjecting it to hot and cold rolling under prescribed conditions. CONSTITUTION: An Al-Mn-Cu alloy contg., by weight, 0.3 to 2% Mn and 0.2 to 1% Cu is used as a core material. The core material is subjected to homogenizing treatment at ≥560°C. The core material is then clad with an Al brazing filler metal and is subjected to hot rolling. It is then subjected to cold rolling at 20 to 70% rolling rate and is finally subjected to annealing treatment at 300 to 480°C. COPYRIGHT: (C)1990,JPO&Japio

Low melting low silver brazing filler metal

Abstract: PURPOSE:To decrease an Ag content and to improve workability by forming a silver brazing filler metal of specific weight % of Mn, Ag and Cu and adding prescribed % of Ni and >=1 kinds among tin, lead zinc, In, and Bi groups thereto as necessary. CONSTITUTION:The component compsn. of this silver vrazing filler metal is comoposed, by weight of 0.1-45% Mn, 1-30% Ag, and the balance Cu and unavoidable impurities. The brazing filler metal is further made of the compo nent constitution added with either of both of 1-15% Ni and 1-45% >=1 kinds among tin, lead, zinc, In, and Bi. The m. p. of the silver brazing filler metal is lowered and the wettability and penetratability are improved by compounding respectively adequate ratios of Mn, Cu, Ni, tin, lead, zinc, In, and Bi therewith. The Ag content is, therefore, decreased and since the brazing filler metal does not contain harmful elements such as Cd, the workability of brazing is improved.

Aluminum alloy filler metal

Abstract: PURPOSE:To improve weld crack sensitivity by constituting a filler metal of an Al alloy compsn. which contains respectively specific weight % of Zr, Mg and Ni and is added with respectively prescribed of Mn, Ti, etc., at need. CONSTITUTION:3.0-10.0(wt%, hereafter the same) 0.006-3.0% Ni, and 0.5-1.2% Zr are incorporated as the component compsn. into the filler metal and either of 0.05-1.5% Mn and 0.01-0.5% Cr is incorporated therein at need. Or 1 or >=2 kinds of 0.005-0.2% Ti and 0.001-0.01% B are added thereto at need and the balance is composed of Al and impurities. Such compsn. is extruded by a pressurized solidifying and extruding method, etc., to form the filler metal. Since an adequate ratio of the Zr is incorporated into the filler metal, the finer crystal grains are formed in the weld zone of the Al alloy material using such filler metal and the improvement in corrosion resistance, strength, etc., is attained by the additives thereof, by which the weld crack sensitivity thereof is improved.

Light-water nuclear reactor vessel and process for its manufacture

Abstract: A vessel comprising a shell of large thickness, for example between 200 and 300 mm, consists of unit components symmetrical in revolution (2a, 2b, 6, 7, 8, 9, 10, 3a, 3b) and connected together by end-to-end welding. The components are made of a steel containing 2 to 2.50% of chromium, 0.9 to 1.1% of molybdenum and less than 0.15% of carbon. The welding for connecting these unit components is performed by means of an electron beam in a single pass over the entire thickness of the components, without filler metal. the invention applies particularly to the manufacture of a vessel for a pressurized-water nuclear reactor.

Computer control of gas metal arc welding

Abstract: The state of an arc weld is determined by the composition of the weld and base metal and its thermomechanical history. The composition of the deposited weld metal depends primarily on the amount of filler metal dilution which occurs. The heat input to the weld, comprising pre-heat and process heat, is the controlling factor in the thermal cycle to which the material responds metallurgically, to produce a specific set of weld properties. Thus, control of the arc welding process should focus on rational specification and real-time control of the heat and mass input to the weld. A process control model has been developed for the gas metal arc welding (GMAW) process using the state variables, time-domain method. The governing equations have been solved for the process parameters as functions of the desired heat input (in terms of heat per unit length) and mass input (in terms of transverse reinforcement area) to the weld. The resulting nonlinear model has been used with a simple proportional controller with deadband and variable coefficients to control the weld heat input and reinforcement area independently. A welding machine has been developed for this work, consisting of a computer-controlled welding head, positioning table, and operator panel,more » which is the front end for a conventional 300 A constant voltage power supply. Software for the system is written in the HPL language. System components communicate over an IEEE-488 bus. 9 refs., 6 figs.« less

Method of forming a joint between aluminum workpieces with curable adhesive and resistance welding

Abstract: The invention concerns a method of forming a joint between aluminium workpieces. These carry an artifically applied e.g. chromate or anodic oxide coating on their surface. A curable adhesive containing up to 40% by weight of particulate filler having a maximum particle size of 300 microns is provided between the workpieces to be joined. Resistance welding is performed using a welding electrode whose tip has a surface with an average roughness depth of at least 10 microns. This increases electrode life and makes it possible to use lower welding currents than previously recommended.

Electrode carrying wire for GTAW welding

Abstract: A welding torch for gas tungsten arc welding apparatus has a hollow tungsten electrode including a ceramic liner and forms the filler metal wire guide. The wire is fed through the tungsten electrode thereby reducing the size of the torch to eliminate clearance problems which exist with external wire guides. Since the wire is pre-heated from the tungsten more wire may be fed into the weld puddle, and the wire will not oxidize because it is always within the shielding gas.

Silver alloy filler metal for brazing

Abstract: PURPOSE:To reduce roughness and ruggedness after brazing and to inhibit tarnish and corrosion by residual cleaning soln, by specifying the compsn of an Ag alloy filler metal for brazing CONSTITUTION:This Ag alloy filler metal for brazing has a compsn consisting of, by weight, 20-55% Cu, 3-15% In, 0001-15% P, 0001-10% Si and the balance Ag The reason that P and Si are contained in the Ag alloy filler metal is that P and Si reduce the surface tension of the filler metal during brazing, suppress the surface roughening of the filler metal and inhibit the occurrence of ruggedness The P and Si contents are limited because 15% P or >10% Si enhances the flowability of the filler metal By the enhanced flowability, the filler metal flows to a part of a base metal not to be brazed and deteriorates the corrosion resistance and fine appearance In addition, >15% P or >10% Si forms a P-Si compd on the brazing interface and imparts unfavorable influence on brazing strength

Production of heat exchanger

Abstract: PURPOSE: To improve the corrosion resistance in the joint part of an extruded pipe of an Al metal provided with a Zn base metal layer on the outside surface and piping joints by brazing the joints to both ends of the extruded pipe after removing the Zn base metal layer therefrom at the time of producing a heat exchanger by using the extruded pipe. CONSTITUTION: The Al alloy extruded pipe 8 provided with the Zn or Zn alloy layer on the outside surface is formed zigzag and corrugated fins 11 are inserted therebetween. Further, the Al alloy joints such as unions 9 and nuts for connecting to an external piping are assembled to both ends of the extruded pipe 8 and are coated with a fluoride flux; thereafter, the pipe and the joints are heated and brazed in an N 2 atmosphere by using an Al-Si alloy brazing filler metal 7. Preferential corrosion 13 of the brazed part is significant when the Zn diffused layer 12 having ≥0.5wt.% surface Zn concn. exists at the joint boundary of the pipe 8. The Zn or Zn alloy in the Al alloy joint parts at both ends of the pipe 8 is, therefore, removed by a physical, chemical or other method and thereafter, the Al alloy joints are brazed. COPYRIGHT: (C)1990,JPO&Japio

Paste for brazing

Abstract: PURPOSE: To manufacture paste for brazing for joining ceramic and metal under good condition by manufacturing the paste for brazing with titanium powder, silver brazing filler metal powder, organic binder and spherical metal powder having the specific diameter. CONSTITUTION: The paste 2 for brazing composing of the titanium particle 21, silver brazing filler metal powder 22, spherical metal powder (titanium, stainless steel, etc.) or inorganic material powder (zirconium oxide, etc.) 23 having ≥30μ diameter, organic binder and organic solvent, is manufactured. This paste 2 is coated to one side surface of alumina substrate 1 to join with the stainless steel plate 3 and they are heated at about 800°C for about 1-2min under vacuum of ≤about 2×10 -4 Torr, to vaporize the organic binder and the organic solvent. By this method, the stainless steel plate 3 and the alumina base plate 1 is firmly joined and on the other side surface of the alumina substrate 1, this film thermister element for forming electrode film 11 and temp. element resistant film 12 can be easily brazed as joining with the stainless steel plate 3. COPYRIGHT: (C)1989,JPO&Japio

Precoated brazing filler metal-coated metal sheet, production thereof and using method therefor

Abstract: PURPOSE:To uniformly and simply braze wide joining area of metal sheet at a stroke by coating brazing filler metal suspending in solvent together with organic binder on the surface of the metal plate and removing the solvent by preheating. CONSTITUTION:Coiled stainless steel sheet 1 is rewound and inserted into coating unit 2 and the powdery brazing filler metal (Ni-Cr-P series brazing filler metal, etc.) in a vessel 4, the organic binder (polyvinyl alcohol series, etc.) in a vessel 6 and the solvent are mixed, suspended and coated on the steel plate 1 with spray guns 8. Successively, the continuously running steel sheet 1 is sent into drying unit 10 providing double structure 9 and dried under insert gas atmosphere of Ar, etc., to vaporize the solvent and wound to the coil. By this method, the brazing can be simply executed to the wide joining area of the stainless steel plate 1 under good condition and a heat exchanger is easily manufactured.

One-side welding method for stainless clad steel plate

Abstract: PURPOSE: To efficiently perform one-side welding by filling metal powder with specific composition in a groove and welding carbon steel plates to each other by using submerged arc welding material for stainless steel and welding the groove surface side constituted of stainless steel plates with the same kind of metal material. CONSTITUTION: Stainless clad 1 steel plates formed by cladding the stainless steel plates S on the surfaces of the carbon steel plates C are subjected to one-side welding from the stainless steel plate S clad side. In this case, the metal powder consisting of, by weight, 50W70% Cr, 20W30% Ni and the balance Fe with impurities is filled in the groove. The submerged arc welding material for the stainless steel is then used to weld the carbon steel plates to each other and an austenitic metallic structure containing 3W15% ferrite is obtained. The groove surface side constituted of the clad stainless steel plates is then welded by using the same kind of welding metal material. By this method, weld metal excellent in the corrosion resistance and the impact resistant performance is obtained. COPYRIGHT: (C)1989,JPO&Japio

Manufacture of thin aluminum sheet for brazing

Abstract: PURPOSE:To obtain a thin Al sheet for brazing having high buckling resistance at high temp. and superior pitting corrosion resistance by cladding both sides of an Al alloy as a core material with Al-Si type brazing filler metal and by subjecting the resulting clad material to hot rolling, process annealing, primary cold rolling, process annealing and cold rolling to the final thickness. CONSTITUTION:The compsn. of an Al alloy as a core material is composed of, by weight, 0.6-2.0% Mn, 0.31-0.80% Fe, 0.05-0.6% Si, 0.5-2.0% Zn and the balance Al with inevitable impurities. Both sides of the Al alloy is clad with Al-Si or Al-Si-Mg type brazing filler metal as a shell material to obtain a clad material. When the clad material is hot rolled and cold rolled, cold rolling is carried out once or more at >=40% total draft between process annealing after hot rolling and subsequent process annealing. After the final process annealing, cold rolling to the final thickness is carried out at 10-50% draft. By this method, a thin Al sheet for brazing having high buckling resistance at high temp. and superior pitting corrosion resistance can be manufactured.

Silver brazing filler metal

Abstract: PURPOSE:To improve the reliability of a product by incorporating copper and tellurium and, if necessary, phosphorus, respectively at specific weight % as a component compsn. into a silver brazing filler metal and consisting the balance of a silver component. CONSTITUTION:The copper which improves the basic flow characteristic of the brazing filler metal is incorporated at 5-50wt% and the tellurium is incorpo rated as the element to increase the density of the metallic structure in the brazing filler metal at 0.0001-0.1% into the components of the silver brazing filler metal. The balance of the components is composed substantially of the silver component. The phosphorus to improve the fluidity of the brazing filler metal is further additionally added at 0.001-0.5% thereto at need. The copper component, tellurium and phosphorus component in the components improve the wettability of a joint part and the denser and smoother metallic structure is obtd. if such silver brazing filler metal is used. The joint strength and corro sion resistance are thereby improved. The surer joining of members is, therefore, executed and the reliability of the product is improved.

Welding tube for heat exchanger and its manufacture

Abstract: PURPOSE:To improve the fitness of a welding tube and seat plate by bending both side parts of an Al made plate stock cladding a brazing filler metal about orthogonally, abutting the tip part to opposed wall faces and brazing it integrally. CONSTITUTION:An Al made plate stock in long size is prepd., subjected to bending orthogonally in the same direction so as to form a wall face 22 as well and after joining tip parts 31, 31 a tip 32 is abutted to the opposed wall face 23. In this case, a weld zone 21 is formed at the inside of about center part of the wall faces 22, 23 and its tip 32 is integrally brazed with the weld zone 21 as well. This welding tube 20 is inserted into the fitting hole 26 of a seat plate 25 and then the defective brazing of a brazing filler metal at brazing time is prevented because of the outside seam part 27 of the weld zone 21 becoming almost on the same level. Due to the weld zone 21 abutting to the wall face 23 the recess to the inner side of the wall face 23 is not caused. Consequently the fitness of the tube 20 and seat plate hole 26 is improved.

Heat treatment for welding zone

Abstract: PURPOSE:To improve toughness in a weld zone and also to relieve residual welding stress, by subjecting a heat-transfer pipe of a heat exchanger and a hub of a pipe plate to butt welding and then applying heat treatment to the weld zone under specific conditions. CONSTITUTION:The heat-transfer pipe 2, composed of high-Cr steel containing, as principal components, 8.0-10.0wt.% Cr and 0.8-1.2wt.% Mo, of a heat exchanger and the hub 3a of a pipe plate 3 composed of high-Cr steel are allowed to abut each other and subjected to inert-gas tungsten-arc welding by the use of filler metal. Subsequently, the weld zone 4 is rapidly heated up to a temp. in a temp. region of the Ac3 transformation point or above, 900-960 deg.C, from the inside by means of a high-frequency heater 6, and the outside is cooled rapidly down to ordinary temp. by passing water 10. Further, high-frequency heaters 6, 7, 8 are electrified, and a residual welding stress zone 9 including the weld zone 4 is heated from the inside up to 700-760 deg.C and then cooled slowly. In this way, a coarse-grain zone in the weld zone 4 is refined and formed into a stable tempered martensite structure, so that toughness is improved and residual welding stress is relieved.

Production of laminated heat resistant alloy plate

Abstract: PURPOSE:To surely form a good joining part by superposing an upper plate via a Ni brazing filler metal by forming numerous fine grooves on the Ni alloy plate in the specified thickness and executing pressurizing and heat treatment under the specified conditions by facing the groove downwards. CONSTITUTION:Numerous fine grooves C are formed at fixed intervals on the Ni alloy plate 4 in 0.5-5.0mm thickness and the upper plate 5 having the same or different material as or from that of this fine grooved plate is super posed so as to cover the groove C via a Ni brazing filler metal. For the Ni brazing filler metal an acrylic resin is blended at about 10:1wt.% with the powder of a Ni solder BNi-2, etc., and solidified in a sheet shape is used. The uniform loading load >=30g/cm is exerted on the fine grooved plate 4 by divid ing the load area into by plural blocks and it is subjected to heat treatment for 5-60min at 1,000+ or -20 deg.C under inert atmosphere or vacuum, 15-60min at 1,050-1,150 deg.C thereafter and further >=2hr at 1,060-1,140 deg.C. On completion of the heat treatment it is left for cooling to about 900 deg.C inside heating chamber, then rapidly cooled under reducing gas to about 200 deg.C to make at <=about 200 deg.C and fetched out of the heating chamber.

Aluminum alloy filler metal

Abstract: PURPOSE:To prevent a welding crack and the transfer of a bead trace by containing a Zn Mg, Cu, Cr, Ti and B at a specific wt.%, adding more than one kind of Zr and Mn of a specific % and making the balance Al. CONSTITUTION:The composition of an Al alloy filler metal contains 3.0-8.0(wt.% is same on the rest)% Zn, 0.5-5.0% Mg, 0.3-3.0% Cu, 0.05-0.35% Cr, 0.001-0.2% Ti, 0.0001-0.01% B and the balance is formed with Al and impurities. More than one kind of 0.01-0.4% Zr and 0.01-1.0% Mn is added further, if necessary. The Zn, Mg, Cu in the components act as a strength improving element all together, Cr improves the corrosion resistance and Ti, B refine the crystal grain. Zr, Mn improve the welding crack resistance and corrosion resistance. A welding crack and the transfer of a bead trace are thus prevented.