Search Results for filler metal selection

This article provides a comprehensive matrix for selecting an aluminum filler alloy for the gas tungsten arc and gas metal arc welding processes, based on the various requirements or service conditions. A table lists the nominal strengths of aluminum filler metals.

Fabrication of high-density heat exchangers, which have a large heat transfer area and a compact size, is best accomplished by brazing where the brazing filler metal is clad to the materials to be brazed. This article focuses on the brazing procedures involved in the fabrication of high-density heat exchangers. The brazing procedures include base metal and brazing filler metal selection; fabrication of clad brazing materials; and stamping, cleaning, and assembling of cladded parts. The article concludes with an examination of brazing parameters.

Repair welding is a necessary operation for most fabricators and can cost more than the price of the original component if performed improperly. This article provides a discussion on the repair welding of castings for ferrous and nonferrous materials. The discussion focuses on the surface preparation, weld repair process selection, joint selection, filler metal selection, weld repair considerations, deposition techniques, postweld heat treatment, and verification of weld repair quality.

This article provides a discussion on filler metal selection, brazing procedures, and brazing equipment for brazing refractory metals. These include molybdenum, tungsten, niobium, and tantalum, and reactive metals. Commercially pure and alpha titanium alloys, alpha-beta alloys, zirconium alloys, and beryllium alloys are some reactive metals discussed in the article.

The various methods of furnace, torch, induction, resistance, dip, and laser brazing are used to produce a wide range of highly reliable brazed assemblies. However, imperfections that can lead to braze failure may result if proper attention is not paid to the physical properties of the material, joint design, prebraze cleaning, brazing procedures, postbraze cleaning, and quality control. Factors that must be considered include brazeability of the base metals; joint design and fit-up; filler-metal selection; prebraze cleaning; brazing temperature, time, atmosphere, or flux; conditions of the faying surfaces; postbraze cleaning; and service conditions. This article focuses on the advantages, limitations, sources of failure, and anomalies resulting from the brazing process. It discusses the processes involved in the testing and inspection required of the braze joint or assembly.

This article is a guide to the welding of commercially available aluminum-lithium alloys. It discusses the weldability issues created by weld porosity, hot cracking, and filler metal selection and presents the data revealed from weld characterization.

Cast irons and carbon steels are brazeable materials, although the brazeability of cast iron is lower than that of carbon steel. The article provides a detailed discussion on the brazeability of different types of cast iron (malleable iron, ductile iron, and gray iron), carbon steels, and dissimilar metals. It describes the factors considered in the selection of filler-metal for cast iron and carbon steel brazing, such as temperature and environment, brazed joint design, heat source, and heat-treatment requirements. The article also discusses the basic considerations in cleaning and fixturing procedures, filler metal and flux/atmosphere feeding procedures, and the heating methods of cast iron and carbon steel brazing.

Torch soldering utilizes a fuel gas flame as the heat source in the soldering process to produce a leak-tight assembly with some degree of mechanical strength. This article describes the advantages, limitations, and applications of torch soldering. It reviews the equipment used and the basic heating techniques required for the soldering.

Exothermic brazing is a process that utilizes the heat produced in a solid-state chemical reaction to melt a conventional filler metal or to produce molten filler metal as a product of the reaction. This article provides the pros and cons of exothermic brazing, describes procedure of the process, and illustrates a typical arrangement for the exothermic brazing of tube. It provides information on the exothermic compounds used for brazing refractory metals and aluminum alloys.

The aluminum alloy 4043 is recommended as a filler metal when resistance to salt water corrosion is required, especially when welding such aluminum alloys as 5052, 6061, and 6063. This datasheet provides information on key alloy metallurgy, and processing effects on tensile properties of this 4xxx series alloy.

Zirconium and its alloys are available in two general categories: commercial grade and reactor grade. This article discusses the welding processes that can be used for welding any of the zirconium alloys. These include gas-tungsten arc welding (GTAW), gas-metal arc welding (GMAW), plasma arc welding (PAW), electron-beam welding (EBW), laser-beam welding (LBW), friction welding (FRW), resistance welding (RW), resistance spot welding (RSW), and resistance seam welding (RSEW). The article reviews the selection of shielding gases and filler metals for welding zirconium alloys. It concludes with a discussion on process procedures for welding zirconium alloys.

This article presents an overview of resistance brazing (RB) used for many applications involving small workpieces, for small joints that are part of very large equipment, or for low-volume production runs. It lists the advantages and limitations of RB and outlines the factors that contribute to high quality in an RB joint. The article discusses the classification of RB such as manual RB or automatic RB. It describes the selection of metal electrodes and filler metals for RB. The filler metals include silver alloys, aluminum-silicon alloys, and copper-phosphorus alloys.

Brazing and soldering are done at temperatures below the solidus temperature of the base material but high enough to melt the filler metal and allow the liquid filler metal to wet the surface and spread into the joint gap by capillary action. This article discusses the common advantages of both brazing and soldering. It describes the brazing and soldering of cast irons, as well as the selection of brazing filler material. The article discusses various brazing methods: torch brazing, induction brazing, salt-bath brazing, and furnace brazing. It concludes with information on the application examples of brazing of cast iron.

The quality of brazed stainless steel joints depends on the selection of the brazing process, process temperature, filler metal, and the type of protective atmosphere or flux. This article provides a detailed discussion on the applicability and brazeability of stainless steel and lays an emphasis on the selection of suitable filler metal, brazing processes, and its corresponding furnace atmosphere for brazing different grades of stainless steel. The types of brazing processes include torch brazing, furnace brazing in different atmospheres (dissociated ammonia, dry hydrogen, and vacuum atmosphere), dip brazing in salt bath, and high-energy-beam brazing. A complete list of the typical compositions and properties of standard brazing filler metals for brazing stainless steel is also provided.

The process of making assemblies of solid-solution and precipitation hardening groups of alloys and superalloys often requires welding of dissimilar metals, welding of diffusion-bonded materials, and sometimes weld overlay cladding and even thermal spraying that in turn requires special knowledge and treatments developed specifically for each material. This article emphasizes the special metallurgical welding considerations for welding solid-solution and precipitation hardening nickel alloys, cobalt alloys, and superalloys.

This article addresses consumable selection and procedure development for the welding of stainless steels. The WRC-1992 diagram and the Schaeffier diagram, are used to illustrate the rationale behind many filler-metal choices. The article discusses the basic metallurgy and base metals of five major families of stainless steels: martensitic stainless steels, ferritic stainless steels, austenitic stainless steels, precipitation-hardening (PH) stainless steels, and duplex ferritic-austenitic stainless steels. Stainless steels of all types are weldable by virtually all welding processes. The article describes the common arc welding processes with regard to procedure and technique errors that can lead to loss of ferrite control with the common austenitic stainless steel weld metals that are designed to contain a small amount of ferrite for protection from hot cracking. The arc welding processes include shielded-metal arc welding, gas-tungsten arc welding, and gas-metal arc welding.

Stainless steels are an important class of engineering alloys used in both wrought and cast form for a wide range of applications and in many environments. This article aids in the selection of stainless steels based on weldability and service integrity. Stainless steels are classified by microstructure and are described as ferritic, martensitic, austenitic, or duplex. The article illustrates compositional ranges of the ferritic, martensitic, austenitic, and duplex alloys in the Schaeffler diagram. It describes the metallurgical aspects of welded stainless steels to be considered for particular engineering applications and service conditions. The article discusses the microstructural evolution of the weld metal and the heat-affected zone, susceptibility to defect formation during welding, mechanical and corrosion properties, and weld process tolerance.

This article describes the physical principles of brazing with illustrations and details elements of the brazing process. The elements of brazing process include filler-metal flow, base-metal characteristics, filler-metal characteristics, surface preparation, joint design and clearance, temperature and time, rate and source of heating, and protection by an atmosphere or flux. The article explains the different types of brazing processes: manual torch brazing, furnace brazing, induction brazing, dip brazing, resistance brazing, infrared (quartz) brazing, exothermic brazing, electron-beam and laser brazing, microwave brazing, and braze welding.

This article describes general welding characteristics such as weld microstructure and weldability. The correlations of preheating and postweld heat treatment practices with carbon contents and welding characteristics of martensitic stainless steels are reviewed. The article contains a table that lists the electrodes and welding rods suitable for use as filler metals in the welding of martensitic stainless steels. It provides specific arc welding procedural recommendations for the commonly welded martensitic stainless steels. Martensitic stainless steel joining methods such as laser-and electron-beam welding, resistance welding, flash welding, and friction welding, are discussed.

Non-heat-treatable aluminum alloys constitute a group of alloys that rely solely upon cold work and solid solution strengthening for their strength properties. This article focuses on the weldability and weld properties of different classes on non-heat-treatable aluminum alloys.