Welding brass with argon: technology features and practical tips

Among all types of welding, brass welding is one of the most complex technological processes. This is explained by the fact that zinc, which is part of this copper alloy, begins to actively evaporate when heated, which leads to the formation of pores in the weld and, accordingly, to a significant deterioration in the quality and reliability of the joint being formed. Welding brass parts is also complicated by the fact that when it is performed, zinc vapors are released, which are very harmful to human health.

Argon welding of copper alloy

Welding technologies for brass products

As you know, brass is an alloy of copper and zinc. In some cases, when it is necessary to obtain a metal with special characteristics, other chemical elements can be added to it - tin, nickel, lead.

Zinc, which is contained in a significant amount in brass, begins to evaporate when heated strongly, which leads to porosity in the welded joint. In addition, by reacting with oxygen contained in the surrounding air, zinc vapor is converted into the oxide of this metal, which forms a white coating on the surface of the parts being connected. Possessing refractoriness and thereby complicating the welding process, this coating poses a great danger to human health, as it is very poisonous.

Mechanical properties and chemical composition of brass

Taking into account all the above factors, experts have developed several technologies that can effectively weld brass. These include:

• gas and electric arc welding;
• joining brass parts under a layer of flux;
• welding performed in a shielding gas environment, which is most often used argon.

Of all the listed technologies, it is brass argon welding that has become most widespread due to its high efficiency and the ability to obtain high-quality welded joints in any conditions.

Welcome to our store Svarnoy66. is the official representative of GROVERS in Yekaterinburg and the Sverdlovsk region. Grovers are reliable welding machines, high-quality assembly and serious quality control from GROVERS. Whether you are a beginner welder, an amateur or a welding professional, the Svarnaya66 team will help you with the choice of welding equipment and consumables. The Svarnaya66 store always has a wide selection of welding and consumables for MMA MIG TIG welding and CUT plasma cutting. Welding electrodes, rods for TIG welding, welding wire for semi-automatic welding and much more you can find on our website..

One of the common rods for argon-arc welding of stainless steels 308L Corrosion-resistant chromium-nickel rod for welding stainless steels with a chromium content of ~ 18% and nickel ~ 8% type 08Х18Н10, 12Х18Н9Т, 08Х18Н10Т, 304, 308, 347 and them similar in the environment of pure ARGON. Provides high resistance against intercrystalline corrosion. Widely used in mechanical engineering for the petrochemical and food industries, energy, etc. Current = (-) CONSTANT. Available: ø 1.0; 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm ER 308L/AWS

Perhaps the most popular rod for argon arc welding is 308LSi Corrosion-resistant chromium-nickel rod for welding austenitic stainless steels with a chromium content of ~18% and nickel ~8%, type 03Х18Н11, 06Х18Н11, 08Х18Н10Т, 12Х18Н10Т, 304, etc. p. in an ARGON environment. The weld metal 308 L Si has high corrosion resistance. The low carbon content reduces the risk of intercrystalline corrosion, and the presence of silicon ensures high quality welds. It is used in the food industry, petrochemical engineering for the manufacture of pipelines, tanks, boilers, etc. Current =CONSTANT (-). Available: ø 1.0; 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Filler rod 347Si Corrosion-resistant chromium-nickel rod for welding stainless steels with a chromium content of ~ 18% and nickel ~ 8%, type 08Х18Н10, 12Х18Н9Т, 08Х18Н10Т, 304, 308, 347 and the like in an ARGON environment. Alloying with niobium and silicon ensures high resistance to intercrystalline corrosion and high quality welds. Widely used in mechanical engineering for the petrochemical and food industries, energy, etc. Current = CONSTANT (-). Available: ø 1.0; 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Filler rod 318Si Corrosion-resistant rod for welding austenitic stainless steels containing ~19% chromium, ~12% nickel and ~3% Mo in ARGON. The weld metal 318 Si has high corrosion resistance. Alloying the rod with niobium provides high resistance to intercrystalline corrosion; and silicon - high quality weld. The wire is used in the food industry and petrochemical engineering for welding products operating at temperatures up to 400 °C. Current =CONSTANT (-). Available: ø 1.0; 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Filler rod 316 L Si Designed for welding austenitic stainless steels with a chromium content of ~18%, nickel ~8% and Mo ~3% such as: 03Х17Н14М2, 10Х17Н13М3Т, 316, etc. in a PURE ARGON environment. Weld metal type 316Si is highly resistant to corrosion in acid and chlorine-containing environments. Silicon alloying ensures high quality welds. It is used in the chemical and food industries, petrochemical engineering. Current = DC(-). Available: ø 1.0; 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Filler rod 309 LSi Corrosion-resistant chromium-nickel rod for welding dissimilar steels (stainless steels with non- and low-alloy steels), as well as for welding austenitic stainless steels containing ~24% chromium, ~13% nickel and a small percentage of carbon in an ARGON environment. It is used in the chemical and food industries, petrochemical engineering. Current = DC(-). Available: ø 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Filler rod 309 L Corrosion-resistant rod for welding dissimilar steels (stainless steels with non- and low-alloyed), sublayers during cladding, as well as for welding austenitic stainless steels containing: chromium ~24%, nickel ~13% and a small percentage of carbon (10Х23Н18, 20Х23Н13, 20Х23Н18) with similar ones in an ARGON environment. Provides high corrosion resistance of the seam. It is used in the chemical and food industries, petrochemical engineering and shipbuilding. Current =CONSTANT (-). Available: ø 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Filler rod 385 Used for welding austenitic stainless steels containing: Cr ~20%, Ni ~ 25%, Mo ~5%, Cu ~1.5% and a small percentage of carbon in shielding gases: ARGON, Ar / He, He mixtures . The deposited metal has high corrosion resistance, resistance to intercrystalline corrosion and resistance to aggressive environments, significantly exceeding the resistance of stainless steels such as 316L, 318. It is used in the chemical and food industries, petrochemical engineering. Current =CONSTANT (-). Available: ø 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Filler rod 310 Corrosion-resistant rod for welding austenitic heat-resistant steels containing: chromium ~25%, nickel ~20% (10Х23Н18, 10Х25Н20, 20Х25Н20С2) in shielding gases: ARGON, Ar/He, He mixtures. In addition, it is used when welding air-hardening steels such as armor. The weld seam is highly resistant to high temperatures. Used in heavy engineering and energy. Current =CONSTANT (-). Available: ø 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Filler rod 312 Corrosion-resistant rod for welding austenitic stainless steels containing Cr ~ 29%, Ni ~ 9%, in shielding gases: ARGON, Ar / He, He mixtures. Due to the high Cr content, the weld metal has good resistance to oxidation at high temperatures, but is prone to embrittlement when exposed to them for a long time. Widely used when welding dissimilar steels, especially if one of the components is completely austenitic steel, and the other is tool steel, difficult to weld, austenitic-manganese, etc. Current =CONSTANT (-). Available: ø 1.2; 1.6; 2.0; 2.4; 3.2 and 4.0 mm

Features of welding brass products in argon

Brass welding, which is carried out in an inert argon gas environment, is used mainly in cases where it is necessary to connect parts whose thickness exceeds 5 mm. The heat source when using this technology is an electric arc burning between the electrode and the surface of the parts being connected. The electrode is fixed in the conductive clamp of the torch, through the nozzle of which shielding gas is supplied to the welding zone. The weld itself is formed through the use of filler material, the composition of which must best match the composition of the products being joined.

Copper Phosphorus Rod for Brass Welding

Melting of the filler material supplied to the welding zone manually is also ensured by the electric arc burning between the electrode and the parts.

Before you start welding brass, you must thoroughly clean the surfaces of the parts to be joined from dirt and oxide film. An indicator of the quality of such cleaning is the metallic shine that should appear on the surface of brass products. The oxide film from brass workpieces is easily removed using nitric acid. After such treatment, it is necessary to rinse the surfaces with hot water.

When welding brass products, you can hear an unusual crackling noise: it is caused by the active release of zinc vapors. Zinc vapor, in addition, colors the welding arc in an unusual color, which is clearly visible even in the video of this process.

Approximate modes for welding brass with a tungsten electrode

The technology for welding brass products is also different in that the connection is made not with a continuous seam, but with separate beads, carefully filling the gap between the parts to its entire depth with molten filler material. It is necessary to comply with this requirement because when making a continuous seam there is a very high risk of burning through the parts being connected.

There is one more rule that must be followed when welding brass products. When filling the weld crater with filler material, you must gradually reduce the arc voltage and increase its length, and then simply move the electrode to the side. You can see how this is done practically in the training video.

It is possible to weld brass products at home, but you should take into account the high health hazard of zinc fumes. That is why it is best to perform this process, if you do not have a workspace with exhaust ventilation at home, in the open air. In any case, wherever parts made from this alloy are welded, the welder should use a respirator.

Varieties

Argon welding wire comes in several different types. The main difference is the content of alloying elements in the composition. Low alloy TIG wire is better suited for welding pure metals rather than alloys. A small amount of alloying improves welding properties and almost does not change the composition of the base metal. But this applies mainly to steels, since when welding aluminum it is desirable to have wire with additional alloying, since it has poor joining properties.

Welding aluminum with argon and filler wire

One of the most common options is wire with a medium level of alloying. After all, many technical metals have exactly this level. These can be various steels that are used in industry. The level of weldability here is not at its highest point, but it is not as bad as that of other metals. So with additional fluxes you can get a fairly good connection.

Wire with medium alloy level

High alloy filler materials are used for the most difficult situations where the metal has poor welding properties. Here, alloying elements help overcome burnout that occurs when exposed to high temperatures. They compensate for the lost elements, thereby improving the connection.

High alloy filler wire for argon welding

Many brands are available in two varieties, with a regular and copper-plated surface. The latter help reduce contact resistance when igniting the arc.

Copper-clad filler wire for argon welding

Advantages of argon arc welding of brass parts

It is no coincidence that argon arc welding of brass products, carried out with non-consumable electrodes, is so popular. The advantages of this technological process are as follows.

• To weld brass in an argon environment, neither specially coated electrodes, which are quite expensive, nor flux are required.
• This technology for connecting parts made of brass is one of the cleanest from an environmental point of view.
• Argon welding is characterized by high speed of execution.
• Welds obtained by argon welding are distinguished by high aesthetic characteristics.
• There is no slag crust on welds made using this technique, which must be cleaned.
• The edges of the connected brass parts are reliably protected from the formation of oxide and nitride crusts through the use of inert gas.
• A jet of argon supplied to the welding zone blows out all waste from the technological process.
• This welding method is universal: it can be used to connect both small and large brass products and restore them using the surfacing method.

Welding materials for TIG welding

Wire for TIG (argon arc) welding is supplied in 1000 mm rods with the following diameters: 1.6; 2.0; 2.4; 3.2; 4.0 mm. Table 1 shows the brands and purpose of the rods

Table 1

Tungsten electrodes:

Conformity table for various standards:

table 2