Influence of nozzle temperature and volumetric filling on the mechanical properties of 3D-printed PEEK

Abstract Fused deposition modeling is a layer-by-layer 3D printing technology used to additively manufacture polymers. A major benefit of 3D-printed polymers is the option of tailoring their mechanical properties by varying the process parameters. In addition, the present study investigates the influence of the filling degree (50 % or 100 %) and the nozzle temperature during manufacturing on the mechanical properties of 3D-printed poly-ether-ether-ketone (PEEK) material. PEEK samples were built either compact (filling degree 100 %) or closed-cell porous (filling degree 50 %), using three different nozzle temperatures (390 °C, 430 °C and 470 °C). In static bending tests, the bending properties were evaluated and compared with injection molded PEEK samples. Bending strength and modulus increased up to 21.1 %, when the nozzle temperature was increased and up to 40.8 % when the volumetric filling was altered. The results indicate that nozzle temperature and volumetric filling can be altered to tailor the bending properties of 3D-printed PEEK for particular applications. However, the mechanical properties of the 3D-printed samples determined in the current study could not achieve those of the properties of the injection molded PEEK.