Magnetic Pinch Force Dynamics
The magnetic pinch force arises from the interaction of electric current and magnetic field, causing a radial constriction of the droplet and the arc column in spray or pulsed arc. It is crucial for droplet transfer.
Physicochemical mechanism of action
The magnetic pinch force arises from the interaction between an electric current and the magnetic field it generates. This leads to a radial constriction of the molten droplet and the arc column in spray or pulsed arc.
Metallurgical relevance & risks in welding
Insufficient magnetic pinch force can lead to uneven droplet transfer, resulting in porosity and distortion of the weld. On the other hand, excessive pinch force can cause overly rapid cooling of the droplet and the formation of glass-hard martensite with increased cracking susceptibility.
Workshop practice & action instructions
To ensure optimal magnetic pinch force, the electric current and magnetic field should be adjusted so that uniform constriction of the droplet and arc column is achieved. This requires careful adjustment of the current and magnetic field strength depending on the specific material properties and the desired welding process.