In MIG welding, what contributes to the distortion of metal?

Excessive heat input during the welding process is a primary contributor to the distortion of metal in MIG welding. When a welder applies too much heat to the metal, it causes the base material to expand significantly. As it cools, the metal contracts. This expansion and contraction can lead to warping, bending, and other forms of distortion in the welded joints and adjacent areas. Proper heat management is crucial for maintaining the integrity of the workpieces, ensuring that the weld does not compromise the structural alignment or dimensions of the materials involved.

In contrast, while factors like voltage and the welder's comfort level can influence the overall weld quality, they do not directly cause distortion in the same way that excessive heat does. The welding torch type might impact the quality of the arc or the bead appearance but is less likely to be a determining factor in terms of heat input and resulting distortion.