Glossary
Welded mechanical parts - Fatigue design of welded joints and harmfulness of flaws

Membrane stress; Membrane Stress

In a wall subject to normal stress variation according to its thickness, average value obtained after linearization.

Bending stress

In a wall subject to normal stress evolution according to its thickness, the value of half the difference between the extreme quantities obtained after linearization.

Primary Stress

Stress (normal or tangential) resulting from mechanical loading and which, as a result, cannot be self-limiting.

Secondary stress

Stress (normal or tangential) resulting from differential deformation (mechanical or thermal) and likely to be self-limiting due to the plastic behavior of the material.

Non-Destructive Testing (NDT)

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