The mechanical properties of additively manufactured dome shaped structures reinforced with cellular patterns: a comparative study when fabricated with planar and curved layers

Thin shell elements are widely employed across various industries due to their favorable aerodynamic and mechanical properties, leading to significant interest in their fabrication. Additive manufacturing offers design freedom and flexibility, positioning it as a promising method for producing these structures. However, components fabricated through additive manufacturing are inherently anisotropic, making it essential to characterize their mechanical properties and understand the influence of the fabrication process on performance, particularly for end-use applications. Among thin shell geometries, dome-shaped structures are particularly relevant due to their structural efficiency and widespread use in lightweight applications. Non-planar layer deposition has demonstrated mechanical and geometric advantages in the fabrication of thin shell structures. Consequently, this study focuses on evaluating the mechanical properties of curved elements fabricated using both planar and non-planar layer strategies. For this, dome-like structures were mechanically characterized when fabricated with planar and non-planar fused filament fabrication processes. Additionally, the effects of cellular reinforcement, incorporating hexagonal, square, and re-entrant patterns, were explored to study their influence on stiffness and deformation mode. The results showed that dome-shaped structures with cellular reinforcement resulted in higher peak loads and enhanced post-yield behavior than solid arrangements. Also, the domes fabricated with planar layers exhibited higher stiffness compared to those fabricated with curved layers, with a difference of 16% for solid, non-reinforced domes with a thickness of 4 mm and 24% for structures with a 2 mm thickness. Furthermore, different deformation modes were observed for each manufacturing method and were compared against finite element simulations.