What is undercut in welding?

In welding, an undercut refers to a groove or indentation that is formed along the base metal next to the weld bead. Undercuts can weaken the strength of the weld joint and lead to issues such as cracking, porosity, and incomplete fusion.

Undercuts are typically caused by improper welding techniques, such as using excessive heat or welding too quickly. They can also occur as a result of incorrect electrode angle, improper welding position, or insufficient filler material.

To prevent undercuts, welders should ensure that they are using the appropriate welding parameters and techniques for the specific type of base metal and welding process being used. It is also important to maintain a consistent travel speed and maintain proper electrode angle throughout the welding process.

If an undercut is detected during the welding process, it is important to address it immediately by adjusting the welding parameters or technique to prevent further undercutting. Grinding or filling in the undercut may also be necessary to repair the weld and ensure its integrity.