How to weld steel?

MIG/MAG welding

The MAG process is the most widely used for welding carbon steels using a gas mixture: Argon/CO2 or Argon/O2.

Ternary Argon/CO2/O2 mixtures can also be used. This mixture can vary depending on the alloys of the materials to be welded, but also on the type of filler metal (solid wire or flux-cored wire), and the different industrial welding conditions (semi-automatic or robotic).

Metal transfer is affected not only by the welding current but also by the oxidant content of the gas in the argon.

TIG welding

TIG welding is mainly used for thin materials, generally carried out under argon, and is characterised by the quality of the surface finish of the welds obtained. It also ensures compactness (absence of porosity), particularly in the first passes.

Other Welding Processes

Other processes such as plasma or laser welding are suitable for welding structural steels; the energy density generated allows for high performance in terms of feed rate and weld quality.

Spot/resistance welding is also an alternative for welding steel parts, often used in the automotive industry. Heat transfer is achieved through the Joule effect: the current generates heat as it passes through the materials:

• sandwiched between the two electrodes
• until fusion is achieved, creating the weld point.

It is essential to ensure the electrodes are in good condition.

Air Liquide will be very helpful in assisting you in choosing your gases, processes, and filler metal. Don't hesitate to contact our experts or consult our content on our website: stainless steel welding, aluminum welding, metal fusion.