Metal Inert Gas Welding with Spray Arc
A MIG welding process utilizing high current and voltage, resulting in contactless, fine-droplet metal transfer through the arc. It ensures high deposition rates and deep penetration for thicker components.
Spray arc means: high current, short distance, the filler material goes over as a fine mist. The argon shields the melt, otherwise the pool burns up. With this you mainly weld thick plates cleanly and with nice penetration.
Watch out for cooling. Too fast cooling gives you hard, crack-sensitive structure. Too slow and the grain gets coarse, then the weld isn't tough anymore. You want to hit the middle there, depending on the base material.
In practice that means: clean edges, set the gas volume properly, and don't have too much distance to the workpiece. When the arc starts to crackle instead of hum, something's wrong. Then reduce current or check gas.