Welding with inert gas (argon):
Precise connections for a wide range of materials
In contrast to conventional arc welding, where the welding point is only protected by the ambient air, welding with inert gas uses an inert gas. This gas, usually argon or helium, displaces the oxygen from the environment and thus prevents oxidation of the weld.
The result: precise, clean and high-strength weld seams that meet even the highest demands.
In general, eye protection approved for the respective process (e.g. safety goggles, welding helmet) must be worn during welding work in order to avoid eye injuries. The Fa. Lampert has its own range of eye protection systems that are precisely tailored for use with its precision welding machines.
Welding with inert gas
Inert gas welding is the umbrella term for various welding processes, which are described in more detail below. An electric current is used to ignite an arc between a metal workpiece and a welding electrode in an inert gas atmosphere, which leads to localized melting.
There are welding machines or welding processes that work with a consumable electrode, others with non-consumable electrodes (e.g. made of tungsten alloys).
In general, approved eye protection (e.g. safety goggles, welding helmet) must be worn during welding work in order to avoid eye injuries. Lampert offers its own range of eye protection systems that are precisely tailored for use with its precision welding equipment.
TIG welding in general:
TIG welding means tungsten inert gas welding with a non-consumable tungsten electrode. It is also possible to work with filler materials.
All metals and alloys that are generally suitable for fusion welding are suitable for this process. Depending on the alloy and welding process, weldability ranges from non-weldable to conditionally weldable to very suitable. Information on this can be found in the respective material data sheets for the alloys.
There are welding machines that work with direct current (e.g. for various steels, precious and non-ferrous metals), others with alternating current (e.g. for weldable aluminum alloys and other light metals). In addition, there are also welding machines that can handle both direct current and alternating current and can switch between the two processes depending on the laying and setting.
Although Lampert micropulse welding units work exclusively with direct current, the use of special welding curves with high-frequency superimpositions can, in certain cases, make it possible to process light metals (e.g. some aluminum alloys) that would otherwise require an alternating current source.
Argon, nitrogen or helium are most commonly used as inert gases, or different gas mixtures depending on the application.
Advantages of inert gas welding with argon:
Melting with inert gas has a number of convincing advantages that make it an indispensable technique in metalworking. Compared to other welding processes, it offers the following advantages:
- Precise weld seams: The inert gas prevents oxidation of the weld, enabling clean and precise seams with minimal slag formation. This is particularly important for delicate workpieces and applications that require maximum precision.
- High seam strength: The gas-shielded weld seams are characterized by high strength and resilience. They can withstand even extreme stresses and thus guarantee durable and reliable connections.
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Versatile application: Joining with inert gas is suitable for a wide range of materials, from unalloyed steels to aluminum and stainless steel. This makes it a universal process that can be used in a wide variety of industries.
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Clean weld seams: The use of inert gas means that there is hardly any welding spatter or smoke. This results in clean, homogeneous weld seams that are visually appealing and require only minimal post-processing.
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Less welding distortion: The controlled application of heat during fusion with inert gas minimizes thermal distortion in the workpiece. This is particularly important for thin sheets and sensitive materials that can be easily deformed by warping.
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Joining thin materials: Joining with inert gas is ideal for joining thin materials that are difficult to weld using other methods. The precise control of the arc enables clean and strong seams even on delicate workpieces, for which the Lampert micro TIG pulse technology is particularly suitable
- Good penetration: The high energy density of the arc ensures deep penetration of the workpiece material. This results in firm and reliable connections, even with thicker workpieces.
The main processes in inert gas welding: MIG/MAG, TIG and plasma welding
Three processes are combined under the umbrella of welding with inert gas, each of which has its own strengths and areas of application:
- Metal inert gas and metal active gas welding (MIG/MAG): The all-rounder among inert gas welding processes. Similar to MAG, MIG is suitable for a wide range of materials and impresses with its high welding speeds and simple handling. The difference between MIG and MAG lies in the type of gas used: While the inert gas (usually argon or helium) does not react with the materials in MIG welding, the active gas (usually a mixture of argon, CO2 and/or oxygen) has a stabilizing effect on the arc and allows targeted, desired reactions with the workpiece in order to avoid undesirable effects (e.g. spatter or burn-off). Due to the higher possible temperature, MIG is mostly used for non-ferrous metals, MAG mainly for steels of different alloys.
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Tungsten inert gas welding (TIG): The queen of precision. TIG welding enables the finest weld seams, even on delicate workpieces such as stainless steel or aluminum. The arc is generated by a non-melting tungsten electrode, which guarantees maximum precision and control.
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Plasma welding: The powerhouse among inert gas welding processes. Plasma welding is suitable for particularly thick materials and hard-to-reach areas. The arc is focused by a plasma jet, which enables very high temperatures and deep penetration.
- Patented Lampert welding principle as a variant of classic TIG welding
- Lampert welding machines enable TIG welding by means of individual, very short welding pulses, the pulse duration can be freely selected in small steps between 0.1 and 34 milliseconds.
- In contrast to welding with a standing (permanent) arc, the heat development with a Lampert precision welding machine is significantly lower. Minimum material thicknesses of up to 0.1 mm, but also up to a maximum of several millimeters can be welded stably – depending on the selected parameters for pulse duration and current intensity.
- The ability to work reliably with very low penetration depths and low distortion or in highly heat-sensitive areas, while also being able to carry out very fine and controlled welds on very large objects, are the major distinguishing features compared to classic TIG welding machines.
- Welding wires can be used as feed and connecting material at any time.
- Lampert welding equipment is used in industry, research and development, prototype construction, series production, (partially) automated applications, by goldsmiths, silversmiths, watchmakers, dental technicians, orthodontists, model makers, in the field of surface restoration and many other applications.
Material diversity when welding with inert gas:
From steel to stainless steel and aluminum
The possible applications for welding with inert gas are almost limitless. Whether unalloyed and alloyed steels, aluminum and aluminum alloys, stainless steel, copper or copper alloys – welding machines with inert gas join almost all common types of metal safely and reliably.
Steel
Unalloyed and alloyed steels form the basis for joining with inert gas. Their versatility, strength and good welding properties make them the most frequently welded materials. Whether constructions made of unalloyed structural steel, high-strength vehicle parts made of alloy steel or delicate stainless steel constructions – steel offers the right alloy for almost every application.
Aluminum
Aluminum impresses with its low weight and high corrosion resistance. Welding with inert gas has a wide range of applications, from aircraft parts and automotive components to electronic devices and sports equipment. The challenge in welding aluminum lies in its high thermal conductivity, which requires precise and controlled heat input.
Gold, silver and platinum
Welding with inert gas is also used in jewelry production (see PUK6 from Lampert): Fixing welds and repairs, filling defects, filling pores by applying welding wire, and much more can be realized with the PUK 6 – from the smallest repair to series production to the most extraordinary new creation.
Stainless steel
Stainless steel combines elegance with robustness and corrosion resistance. Its use in welding with inert gas ranges from medical implants and food processing machinery to chemical plants and architectural facades. The weldability of stainless steel depends heavily on the alloy composition and requires special know-how and filler materials.
Copper and copper alloys
Copper and copper alloys are characterized by their excellent electrical conductivity and thermal properties. They are used for welding with inert gas in the electrical industry, heating and air conditioning technology and the automotive industry. The challenge in welding copper lies in its high thermal conductivity, which can lead to cracks due to rapid cooling.
Special materials
In addition to common materials, welding with inert gas also offers the possibility of joining special materials such as nickel, titanium and magnesium. These materials require special welding processes and filler materials and are used in areas such as aerospace, medical technology and the chemical industry.
Errors during inert gas welding
The most common errors include
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Pore formation: caused by high humidity or insufficient inert gas supply.
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Inclusions: caused by impurities in the base material or filler material.
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Burn-in notches: caused by too high current or welding speed too slow.
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Excessive asymmetry of fillet welds: caused by inconsistent welding technique or incorrect parameter settings.
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Unsuitable penetration: caused by incorrect weld seam geometry or arc length.
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Spatter: caused by excessive amperage, incorrect wire feed speed or unsuitable technology.
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Cracks: caused by excessive tensile stresses in the workpiece, incorrect welding parameters or unsuitable sequence.
Avoidance of welding defects:
To avoid welding errors, it is important to set the welding parameters such as current, wire feed speed and shielding gas flow rate correctly.
The following points should also be observed:
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Use of clean and dry base material and filler material.
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Ensuring a sufficient supply of shielding gas.
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Application of the correct welding technique for the respective seam geometry.
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Regular inspection of welding equipment.
- Welding work in an environment protected from draughts.
Conclusion: Inert gas welding - an indispensable technique in metalworking
Welding with inert gas is more than just a technique, it is an art that combines precision, versatility and safety. Whether in industry, trade or DIY – joining with inert gas enables stable and durable connections that can withstand even the toughest challenges. With a little practice and the right know-how, you too can immerse yourself in the fascinating world of joining with inert gas and quickly become convinced of the advantages of this versatile technology.