Exploring the dynamic mechanical properties of fused filament fabrication printed polyetheretherketone with various infill patterns

The increasing need for 3D-printed PEEK materials in load-bearing applications underscores the need to examine the impact of dynamic loading effects. This study focuses on exploring the dynamic mechanical properties of fused filament fabrication (FFF) printed PEEK polymer across various infill patterns including line, cubic, hexagon, and grid. Adhering to ASTM standards, PEEK polymer parts were fabricated to assess their tensile, flexural, interlaminar shear and dynamic mechanical properties. FEA analysis was performed to understand the failures in each pattern. The results demonstrate notable differences in performance characteristics among the infill patterns, with the hexagon pattern showing superior results. The hexagon pattern exhibited the highest tensile strength of ca.53 MPa, a modulus of ca.20 MPa, an elongation of 5.02%, a flexural strength of ca.85 MPa, a flexural modulus of ca.27 MPa, and an interlaminar shear strength of ca.10 MPa. The storage modulus, loss modulus, and tan δ varied with the infill pattern, reflecting alterations in the elastic behaviour of the differently patterned PEEK prints. Interestingly, the glass transition temperature (T_g) values exhibited only minor variations despite changes in infill patterns. The hexagon pattern’s superior stress transfer capability is evidenced by its lowest tan δ value and highest storage modulus value at T_g, highlighting its enhanced dynamic mechanical performance. The superior properties of the hexagon infill pattern can significantly enhance the design and functionality of FFF printed components subjected to dynamic loads, making this pattern particularly suitable for critical applications in aerospace, automotive, and medical industries.