Method for determining an acceptable maximum alternating stress for a part subjected to cyclic solicitations; unit for determining such a stress

摘要

Method for determining an acceptable maximum alternating stress (δalt_max) at a point (P) of a part (50) subject to cyclic solicitations (F) wherein: a) assuming that the part has an elasto-viscoplastic (EVP) behaviour, the part is simulated as undergoing constant solicitations equal to a threshold value (Fmoy) during a plateau period (P2); b) on the basis of the results of the simulation, a final static stress (δstat_fin) is determined at said point (P), at the end or after the end of the plateau period; and c) for the point (P) in question, the acceptable maximum alternating stress (δalt_max) is determined using a Goodman diagram, said stress being determined for a static stress equal to the final static stress (δstat_fin), the duration (D) of the plateau period being equal to the duration of solicitation of the samples that were used to establish the Goodman diagram.