PSI - Issue 68

Emanuele Vincenzo Arcieri et al. / Procedia Structural Integrity 68 (2025) 1324–1328 E.V. Arcieri et al. / Structural Integrity Procedia 00 (2025) 000–000

1325

2

It is the responsibility of the designer to correctly estimate the fatigue life of components, even in the presence of damage (Huang et al., 2022; Grbovic et al., 2024). Numerical simulation can assist in this process by providing an accurate estimation of the stress-strain state in a damaged component under service loading, that enables a reliable assessment of its fatigue strength. For this reason, the creation of predictive numerical models has become a primary area of interest (Babić et al., 2018; Cazin et al., 2020; Milovanović et al., 2020; Kastratović et al., 2021; Frank and Weihe, 2023). This study uses finite element analysis to find how the impact speed influences the resulting damage in an hourglass specimen. The hourglass shape was chosen for the investigation since studies on impact damage present in the literature commonly focus on impacts on flat or airfoil-like specimens (Mall et al., 2001; Chen, 2005; Frankel et al., 2012; Zhang et al., 2023). Previous works by the authors investigated the impact of a ball on an hourglass specimen at its minimum cross section (Arcieri et al., 2022, 2023). In addition, Arcieri et al. (2021) and Arcieri and Baragetti (2024) numerically demonstrated that impact speed is one of the most significant parameters affecting the stress state in such specimen after impact. Since the stress concentrations and residual stresses in the damaged specimen affect fatigue strength (Nowell et al., 2003; Ruschau et al., 2003; Duo et al., 2007; Oakley and Nowell, 2007; Fleury and Nowell, 2017) and depend on the damage geometry, this factor was considered in the present work. The results revealed that the relationship between the depth of the dent created by the impact and the impact speed follows a second-degree polynomial equation.

Nomenclature E

elastic modulus

R 2

coefficient of determination

U dent depth after impact (maximum displacement in the minimum cross section of the specimen) v impact speed YS yield stress Poisson’s coefficient

Fig. 1. Finite element model for impact simulation (Arcieri et al., 2021, 2022, 2023; Arcieri and Baragetti, 2024).