S–N curves established from limiting energy in the case of specimens additively manufactured from AlSi10Mg

Abstract

This study investigates the varying thermal response of additively manufactured specimens made of AlSi10Mg and subjected to cyclic loading. It is well known that the thermal response is driven primarily by the self-heating effect. The paper explores the possibility of employing thermographic methods to establish an S–N curve for fatigue life prediction with the use of fewer specimens than are traditionally required for an S–N curve established from constant-amplitude fatigue tests. Specific self-heating step tests are conducted by gradually increasing the loading amplitude while monitoring the temperature of the specimen. A new approach is introduced to assess the lower limitation of the existing Fargione method, which addresses the absence of the fatigue limit threshold in previously published works. The validity of this approach is compared with our own experimental data. This new dataset concerns additively manufactured (AM) specimens made from AlSi10Mg powder, which were all printed on a single platform. To observe the sensitivity of the updated approach, four groups with different heat treatments were evaluated.