Filler Metals

metalsFiller Metals
However, you do have to give some care to the preparation of the tubes for brazing.  After you`ve gotten rid of the flux, use a pickling solution to remove any oxides that remain on areas that were unprotected by flux during the brazing process. The best pickle to use is generally the one recommended by the manufacturer of the brazing materials you`re using. Once the flux and oxides are removed from the brazed assembly, further finishing operations are seldom needed. To get a more balanced picture of the overall brazing process, it`s important to note that in most day-to-day brazing work, these steps are accomplished very rapidly.Brazing is a metal joining processes, which is done by using the filler metal.  Fluxing is usually no more than a fast dab of a brush or dipping ends of the parts in flux. And flowing the filler metal is virtually instantaneous, thanks to capillary action. And, as we`ll see later on, these economies in time and labor are multiplied many times over in high production automated brazing. The pure speed of brazing represents one of its most significant advantages as a metal joining process. Contact Us for assistance in assessing your bonding needs and meeting your brazing requirements.Brazing aluminium to copper is common in the refrigeration industry where copper tubes are brazed to aluminium roll-bond panels or tubes.  Please Contact Us to assist you with this specialized braze process and for any vacuum braze processing requirements you may have. When brazing the component metal surfaces, they must be heated over the filler melting temperatures, typically above 850ºC, and even higher for the Ni-based filler metals. When heating to these temperatures, a flux or atmosphere that chemically or physically reduces the surface oxides that forms the metals is essential for brazing to work.It is important to be able to identify when brazing is suitable for joining copper or copper alloys, how it is applied, and which filler metals to use. In order for a molten filler metal to wet”, which is to flow evenly and adhere as a liquid, the metal surfaces have to be free of oxides. Once the molten filler metal spreads or, via capillary action, is pulled into a joint, the heat source is removed to permit the filler metal to solidify and develop a bond to the metal. Flux brazing normally utilizes more intense heating torches which are normally different that those used in soldering due to the need to melt higher temperature metal filler metals. In the case of active brazing and high temperature Ni-based alloy brazing, vacuum brazing is the only process that works.Both oxygen-bearing and oxygen-free copper can be brazed to produce a joint with satisfactory properties.  The fluxes are normally much more aggressive than solder fluxes due to the need to remove more oxide and to provide a local” atmosphere as the flux heats and interacts with the component surfaces and the molten filler metals. The furnace braze processes listed below all utilize controlled heating furnaces (batch or continuous) where parts are fixtured and heated over the filler metal liquidus temperatures.
The process listed below differentiate themselves by the atmospheres used in the furnace enclosure that interacts with the brazing filer metals and part surfaces. Controlled atmosphere brazing provides an environment that is non-oxidizing and typically reducing in order to clean the metal surfaces being brazed. The cleanest and least oxidizing furnace atmospheres are vacuum; as such, vacuum brazing is being used more often for the braze joining of many components. Thus brazing is used in much more critically stressed joints as opposed to solder bonding.Joint design and component fixturing are more critical in brazing due to the higher temperatures where thermal expansion and thermal expansion mismatch play a larger role. We offer a range of brazing services on-site at our facilities and through affiliated partner facilities. Yes and no.. Harris products advises that the Harris 0® is a low cost alloy suitable for most copper to copper or brass joints where good fit-up exists, and the assemblies are not subject to excessive vibration or movement. Through atmosphere or vacuum brazing, we join metal to metal and ceramic to metal in a controlled environment.Depending on your material type and part geometry, our experienced engineers will select the appropriate brazing method to join custom components. Our active metal brazing process is suited for assembling metal substrates to ceramic parts without metallization and is normally very cost effective. We also offer gold, nickel, silver and copper plating services that comply with military standards (Mil Spec). Is a metal-joining process where an alloy is melted and distributed between two or more metals via capillary action. Is a joining process between a metal and another metal or metal(s) to a ceramic(s).Is a metal to ceramic joining process where an alloy is melted and distributed via capillary action between a ceramic(s) that has been metallized and a metal(s). Is a joining process between a metal and another metal or metal(s) to a ceramic that offers significant advantages, which include extremely clean, superior, braze joints of high integrity and strength. Is a joining process between multiple pieces of metal through the use of a laser. Titanium, palladium, platinum and other metals can also be used as brazing filler metals.Is a joining process between multiple pieces of metal that heats via an arc of electricity jumping from a (tungsten metal) electrode to the metal surfaces you intend to weld - usually Kovar or stainless steel. Is a joining process between multiple pieces of metal, which is produced by the flow of electric current through the resistance of metals, held together under pressure. The issue is further confused by the use of such terms as silver solder.” This is a misnomer, because silver-based alloys all melt well above 450°C and are therefore clearly brazing filler metals. The silver-based alloys are thus designated BAg-x, where x is a number corresponding to a certain alloy composition.
The proper term for all alloys used for brazing, including silver-based alloys, is brazing filler metals.”AWS has developed a designation system for brazing filler metals which uses the primary element(s) and a number for unique compositions of brazing filler metals. Other brazing filler metal families include aluminum-silicon filler metals (BAlSi-x), magnesium filler metals (BMg-x), copper, copper-zinc and copper-phosphorus filler metals (BCu-x, RBCuZn-x, and BCuP-x, respectively), nickel and cobalt-based filler metals (BNi-x and BCo-x, respectively) and gold-based filler metals (BAu-x).Heat for either soldering or brazing can be applied in a number of ways; through flames, by resistive heating, by inductive heating, by use of a laser, by combustion and subsequent radiant heating, etc. High temperature brazing, often used for carbide products, may employ alloys that do not contain silver, but contain rather nickel, copper and manganese.Both soldering and brazing can be done in open air (usually with a flux to reduce surface oxides and enable wetting and flow of the solder or braze filler metal) or in protective atmospheres (e.g. inert, vacuum, or active atmosphere). Both techniques can be used to join many metals and metallic alloys, ceramics, and composite materials, to like and dissimilar materials. Wettability of the substrate by either the solder or brazing filler metal is another key consideration in selecting the appropriate process.Phosphorous contained in phos-copper brazing alloys is a temperature depressant and acts as a fluxing agent, while the silver influences the fluidity and improves ductility of the brazing alloy. Call for a copy of our Performance Chart to get information on general use and learn how silver and phosphorous contents affect brazing alloy flow, filleting, and gap filling. Brazing: A process where similar or dissimilar metals are joined using an alloy that typically includes a base of silver combined with nickel, copper, and zinc. Our webpage is broken down according to the general metal joining applications (see links to the left).Brazing is used for compressors, engine circulation tubes, mining tools, plumbing fixtures, jewelry, musical instruments and a variety of other applications. Welding: A process whereby similar metals are joined using a direct heat source to melt the base metal and filler metal to create a uniform finished product. Superior No. 30 SuperSafe Soldering Flux: No. 30 is a great all purpose flux with so many uses and such a great track record that it merits its own page. Aluminum Flux: We supply fluxes for all types of aluminum joining: soldering, brazing and welding.