PSI - Issue 38

Hubert Blondet et al. / Procedia Structural Integrity 38 (2022) 526–537 Hubert Blondet, Kamilia Barthoux/ Structural Integrity Procedia 00 (2021) 000 – 000

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3.1 Build Material Curve – Dimensionless Wohler curve Because cylinder head is submitted to both traction and compression solicitation, stresses have been divided by the Rm in tension or in compression as explained before. Damage can be then computed based on a single dimensionless Wohler curve

Figure10: life Reversals to failure

This dimensionless Wohler curve is built using the following EN curve coming from measurements. Elastic Strain Regression is used (pink triangles): strains are transformed into stresses (σ= E.ε) . Stresses are divided by the tensile Rm. “Life, Reversals to Failure” are transformed into Number of Cycles (Ncycles = 0.5*Life, Reversals to Failure”

Figure 11: Global Process – “LTA” Damage Computation – Dimensionless Wöhler Curve