Preliminary Investigation of Process Parameters for Printing High Performance Single- and Multi-material 3D-Printed Parts Using PEEK and PEI

High-performance polymers, particularly Polyetheretherketone (PEEK) and Polyetherimide (PEI), are very suitable for engineering applications due to their exceptional mechanical and thermal properties. Therefore, combining them in a single build process could be a strategic solution that can exploit the superior mechanical strength of PEEK, despite its printing challenges, while leveraging PEI’s excellent surface finish and ease of printing. However, the processing challenges of these materials require careful control over printing parameters to achieve the desired part qualities. Therefore, this preliminary study aimed to define the feasible process parameter ranges for printing the parts with a multi-material infill strategy. The article focused on selecting print materials and varying three process parameters: infill pattern, infill percentage, and chamber temperature. Samples were printed using three infill patterns (rectilinear, fast, and full honeycomb), two infill percentages (40% and 100%), and three chamber temperatures (155 °C, 185 °C, and 210 °C). Tensile tests were performed, and main effect plots were used to analyze the effect of varying each process parameter on the Ultimate Tensile Stress (UTS) and elastic modulus (E) of printed parts. Based on the analysis, a reasonable range of process parameters is selected to conduct the study on investigating the feasibility of a multi-material printing strategy.