← Glossary

SN Curve (Wöhler Curve)

The Wöhler curve shows the fatigue behavior of metals under cyclic loading. It graphically links stress and number of cycles to failure to determine service life under repeated loads.

Physical-Chemical Mechanism of Action

The Wöhler curve shows the relationship between stress and the number of cycles to failure. It tells you how many cycles a material can take before it breaks.

Metallurgical Relevance & Welding Risks

If you don't know the Wöhler curve well, metals can fail by fatigue under cyclic loading. This can be especially dangerous in machine parts and components under high stress.

Workshop Practice & Action Guidelines

To determine the life of a part, use the Wöhler curve to find the maximum allowable stress for a given number of cycles. Pay attention to proper welding technique and material selection to optimize fatigue behavior.

MetallurgieSchweißtechnik

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