Arc Blow
Arc blow occurs due to uneven magnetic fields that deflect the welding arc sideways, leading to porosity. This happens when the magnetic field is not symmetric or is influenced by metal geometry.
Physicochemical mechanism of action
Arc blow is caused by uneven magnetic fields that deflect the welding arc to the side. This deflection makes the arc no longer hit directly on the workpiece surface, leading to porosity in the weld.
Metallurgical relevance & welding risks
Uneven magnetic fields can cause arc blow and thus porosity in the weld. These pores can impair the strength and toughness of the material and lead to cracking or failure, especially under load.
Workshop practice & action instructions
To avoid arc blow, the magnetic field must be symmetric and not influenced by the metal geometry. This can be achieved by careful arrangement of magnets and the welding torch. Regular checking of the magnetic field and arc position is essential.