Spray Arc Transition Threshold
The current at which the short-circuit arc transitions to a spatter-free spray arc. Depends on shielding gas and wire diameter.
Physicochemical Mechanism of Action
The spray arc transition is the current value at which the short-circuit arc changes into a low-spatter spray arc. This transition happens when the arc energy is enough to ionize the shielding gas and produce fine metal particles.
Metallurgical Relevance & Welding Risks
Too low a current value can mean the transition does not complete, which leads to spatter and irregular bead appearance. Too high a current value raises the temperature and can lead to overheating and distortion of the workpiece.
Workshop Practice & Instructions
To reach the spray arc transition, the current value should be set so it lies between 10 and 20% of the maximum current. This value varies with the shielding gas (e.g. argon or CO2) and wire diameter. With a fine wire (about 0.8 mm), the optimal current value is about 15% of the maximum current.