PSI - Issue 53

Reza Ahmadi et al. / Procedia Structural Integrity 53 (2024) 97–111 Author name / Structural Integrity Procedia 00 (2019) 000–000

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In the analysis of the two-hole specimen, a noteworthy observation emerges in the form of a smoother fracture surface, distinct from the one-hole counterpart. This distinction may find its roots in several factors, chief among them being the distribution of load and the fracture speed across the specimen as resulted in ACP Post analysis. With two holes present, the applied load is likely to distribute more evenly, reducing localized stress concentrations and enabling a more controlled and gradual failure mode. Moreover, the observation of changing hole diameter at the end of the hole in both one-hole and two-hole specimens is a clear manifestation of stress concentration. 5. Conclusion In this study, the mechanical behavior of un-notched and notched specimens was investigated using thermographic methods. While structures with multiple holes can exhibit complex mechanical responses due to stress field interactions, our findings demonstrated that monitoring temperature variations offers early indicators of localized stress concentrations, which have significant implications for design and safety in notched specimens. Notably, the presence of multiple holes in specimens led to lower damage stress, as observed in two-hole specimens compared to those with a single hole. Although the nature of the 3D printing process makes it challenging to attain complete solidity in printed parts, the difference between the results obtained through Finite Element Modeling (FEM) and the actual experiments turned out to be smaller than anticipated. This suggests that thermography is a powerful and cost-effective tool for assessing the fatigue behavior of 3D printed polymers, offering valuable insights into mechanical fatigue properties based on thermal response. 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