← Glossary

Macroscopic Undercut

A localized groove melted into the base metal at the toe of the weld, caused by improper welding parameters or excessive heat input. It reduces the effective cross-sectional area and introduces unacceptable stress concentrations.

A root notch is a local indentation at the weld transition that weakens the cross-section. It usually occurs due to too much heat, wrong parameters, or an unclean start. If you have one, the weld is a weak point at that spot – the part will tear there under load. So make sure you weld clean and evenly, and grind out the notch if necessary before stressing the weld.

MetallurgieSchweißtechnik

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