PSI - Issue 76

Davide D’Andrea et al. / Procedia Structural Integrity 76 (2026) 151–158

158

Conclusions In this work two sets of PA12 specimens manufactured by SLS process have been characterized. The X and Y printing directions demonstrated to give similar mechanical properties and fatigue behaviours. Thermographic Methods have proven to be effective methodologies to rapidly obtain insights in fatigue life of SLS PA12. The fatigue limit obtained by RTM resulted to be σ 0, RTM = 27.4±2.4 MPa, which is close to the value obtained from conventional CA fatigue tests ( σ 0 = 29.3 MPa), showing a percentage difference of 6.8%. STM yielded a stress limit of σ lim =26.2±2.9 MPa, differing from RTM estimation by 4.7% and from the CA fatigue limit by 11.8%. Considering the damping contribution during fatigue tests , by estimating the Energy Parameter Φ and the different equivalent stabilization temperatures it is possible to estimate fatigue life of the material in short time compared to conventional CA fatigue test campaign, which required a total of 1899 hours, since reaching the run-out threshold at 1 Hz takes approximately 11 days. By contrast, obtaining this information in just 41.3 hours corresponds to a 97.8% reduction in testing time. Further studies will focus on microstructural analysis to correlate material defects with observed temperature trends and mechanical properties. References Avanzini, A., Battini, D., Pandini, S., 2022. Static and fatigue behavior in presence of notches for polyamide 12 (PA12) additively manufactured via Multi Jet Fusion TM process. 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