← Glossary

Mechanical Surface Damage Defect

A scratch on the component surface can lead to a defect that acts as a notch for fatigue fractures. This can cause mechanical stress and possibly cracks in the material.

Physical-Chemical Mechanism of Action

A surface scratch creates an uneven spot that acts as a notch for vibrations. This notch can be enlarged by mechanical load or thermal stress.

Metallurgical Relevance & Risks in Welding

A scratch-induced flaw can increase susceptibility to cracking and fatigue fracture. During welding, these notches can enlarge, raising stresses in the material and increasing the risk of hot cracking.

Workshop Practice & Instructions

Before welding, carefully inspect parts for scratches or other mechanical damage. If such flaws are found, fine-polish to remove the uneven spot. This reduces crack risk and improves weld quality.

MetallurgieSchweißtechnik

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