Shielding effects in multiple fatigue cracks: an experimental simulationof thermal fatigue effects, in stainless steel 304

摘要

This paper investigates the harmfulness of cracks networks using both experiments andrnfinite element analysis. A single array of parallel cracks with a central deeper notch and regularlyrnspaced secondary notches of identical depth is used to investigate crack arrest under fatigue loading.rnTests are carried out on 304 stainless steel using a load shedding program prescribed as a functionrnof central crack depth; this loading program is deduced from the numerical analysis of thermalrnfatigue cracks, in EDF components. The difference in length between the dominant crack andrnsecondary cracks is varied to identify conditions giving rise to crack arrest. Fatigue crack growthrnresults are rationalized using finite element computations of stress field using a visco-plasticrnconstitutive model.