What is

MIG/MAG welding?

MIG/MAG welding: arc welding process using a consumable wire electrode

MIG/MAG welding is a type of gas metal arc welding (GMAW). Gas metal arc welding is divided into metal inert gas (MIG) and metal active gas (MAG) welding. During this process, an arc burns between the workpiece and the melting wire electrode. Thanks to its high deposition rate, MIG/MAG welding is a highly cost-effective process and is used for both manual and automated welding tasks.

MIG/MAG welding

How it works

During MIG/MAG welding, the arc is created by a short circuit when the wire comes into contact with the workpiece. The arc ignites after the short circuit is established and the melting wire serves as the filler metal.

To protect the arc and the weld pool from reactive oxygen in the surrounding atmosphere, shielding gas flows out of the gas nozzle. It covers the weld and, most importantly, prevents the liquid metal (that is, the weld droplets and the weld pool) from oxidizing.

Which gases are used?

MAG welding uses active and highly reactive gases such as pure carbon dioxide or gas mixtures (argon, CO₂, O₂) in varying compositions. The MAG process is suitable for welding non-alloy, low-alloy, and high-alloy steels.

MIG welding, by contrast, uses inert gases (non-reactive gases such as pure argon and helium, or mixtures of the two). This process is suitable for welding materials such as aluminum, copper, magnesium, and titanium.

MIG MAG welding

Setup of a MIG/MAG welding system

Illustration of MIG/MAG welding process

Advantages and disadvantages of MIG/MAG welding

Advantages

  • Easy to learn
  • High welding speed
  • Cost effective
  • High deposition rate
  • Low filler metal costs
  • Well suited to mechanized (e.g., with a carriage) or robot-assisted welding applications
  • Simple ignition of the arc

Disadvantages

  • Requires a protective gas shield, so outdoor use is limited 
  • Arc blow can affect seam quality
  • Seam preparation is crucial to the quality of the seam

Arc types

In MIG/MAG welding, the different arc types are classified based on amperage and droplet transfer. In the lower power range, the droplet transfer occurs during a short circuit (dip transfer arc); in the higher power range, it occurs without a short circuit (e.g., spray or pulsed arc).

Process variations in MIG/MAG welding

Cold Metal Transfer (CMT)
An innovative process featuring a reversing wire motion for precise droplet detachment and low heat input.
Low Spatter Control (LSC)
High-quality weld seams with minimal spattering and increased deposition rate.
Learn more about LSC
Pulse Multi Control (PMC)
Optimized droplet detachment for high welding speeds and consistent seam quality.
Learn more about PMC

What materials are suitable for MIG/MAG welding?

The most commonly used material in gas metal arc welding is steel, but aluminum and stainless steel alloys can also be welded effectively using the MIG/MAG process.

Professional MIG/MAG welding equipment

TPS 500i

  • MIG/MAG welding machine
  • Integrated data documentation
  • Intuitive touch display
Learn more about TPSi

Fortis 400

  • Reliable and stable welding performance for all manual applications
  • Clear digital user interface
  • Full connectivity
Learn more about Fortis
Fronius iWave 300i

iWave 300i

  • Multiprocess PRO welding machine
  • Intuitive menu navigation
  • Can be expanded with optional function packages
Learn more about iWave
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Protective clothing for welders
Welding professionals face a range of challenges in their day-to-day work. UV radiation and welding fumes can pose a significant health hazard unless sufficient protection measures are taken. Having the proper equipment and appropriate clothing is essential to maintaining safe welding conditions.

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