← Glossary

Arc strike

Stray light defects are unintentional arc marks on the part surface outside the weld. They cause local hardening and increase the risk of crack initiation.

Physical-Chemical Mechanism of Action

Stray light defects are caused by incomplete or missing protective measures during welding. The arc light can directly hit the component surface and cause rapid hardening there, as the metal near the light source cools suddenly.

Metallurgical Relevance & Risks in Welding

These local hardenings can lead to crack initiation, especially if they are close to important component structures. The hardness of the hardened spots can be high and impair the mechanical strength of the components.

Workshop Practice & Instructions

To avoid stray light defects, careful light protection measures must be taken during welding. This includes using protective screens or isolating the components. The light source should be positioned so that it does not directly hit the area to be welded. In suspicious cases, the affected areas should be carefully inspected and, if necessary, cleaned.

MetallurgieSchweißtechnik

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