PSI - Issue 53

C.T. Duarte et al. / Procedia Structural Integrity 53 (2024) 299–308 Author name / Structural Integrity Procedia 00 (2019) 000–000

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Fig. 10. Quantitative data of unaged and aged specimens: (a) flexural strength; (b) modulus.

4. Conclusion This study investigated the impact of multi-material architecture and the number of ABS and PLA layers in additively manufactured sandwiches, with a focus on their mechanical properties under seawater ageing conditions. Neat PLA and ABS printed specimens were fabricated as well as multi-material sandwich structures with an outer ABS envelope surrounding a PLA core. This was done to evaluate the effect of the multi-material architecture in the mechanical properties as a function of seawater ageing conditions. The following conclusions can be drawn:  The behaviour up to failure in tensile testing of the hybrid materials showed that the less stiff (PLA) material controls the failure strain. Furthermore, a tendency of increase in the tensile strength and modulus was observed as a function of decreasing the ABS layers and increasing the PLA layers owing to the higher mechanical properties of the PLA. The case with a single ABS layer around a PLA core presented the best results when compared to the neat PLA specimens for the unaged case.  Regarding the flexural properties, similar to the tensile properties, a reduction in ABS presented an increase in flexural strength and stiffness and the single ABS layer case presented the best results for the unaged specimens.  As a function of seawater ageing, all the mechanical properties presented a similar trend to the unaged specimens with the exception that they all were damaged by the ageing process to varying degrees. Generally, the single layer ABS specimen presented the overall best performance as it was able to strike a balance between enough water barrier properties and highest amount of PLA layers in the core. Acknowledgements This work was partially supported by the Brazilian Research Agencies: National Council for Scientific and Technological Development (CNPq) - Grant number 311079/2020-2, and Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ) - Grant number E-26/211.072/2019 and E-26/202.728/2019. References Bandyopadhyay, A., and Heer, B., 2018. Additive manufacturing of multi-material structures. Materials Science and Engineering: R: Reports 129, 1-16. Cavalcanti, D., Banea, M., and Queiroz, H. d., 2020. Effect of material on the mechanical properties of additive manufactured thermoplastic parts. Annals of “Dunarea de Jos” University of Galati. Fascicle XII, Welding Equipment and Technology 31, 5-12. Cavalcanti, D. K. K., de Queiroz, H. F. M., and Banea, M. D., 2023. Performance enhancement of adhesive joints of additive manufactured parts