← Glossary

Root oxidation streak

Oxide stringers at the weld root form due to insufficient shielding gas or backing gas during cooling. They lead to embrittlement and localized corrosion.

Physico-chemical mechanism of action

The oxidation line forms when oxygen comes into contact with the hot steel and the shielding gas or backing gas does not adequately protect the surface. This leads to local embrittlement of the weld root.

Metallurgical relevance & risks in welding

The oxidation line can lead to corrosion and local cracks, especially if not removed. It reduces the strength and toughness of the weld.

Workshop practice & instructions

Make sure that sufficient shielding gas or backing gas is used during cooling. If you spot an oxidation line, remove it by polishing or chemical cleaning.

MetallurgieSchweißtechnik

AI Transparency (EU AI Act): Created on the basis of our own many years of practical experience in welding technology, with the help of AI, and reviewed editorially.

© 2026 Welder-World. All content is for training and continuing education and does not replace a certified welding procedure specification.