Design and Development of 3D Printed PEEK

Biomedical devices have potential to benefit from increased customization and enhanced material quality, which can be implemented using additive manufacturing. Customization of these biomedical devices is necessary to fit the individual constraints of each patient, while material quality dictates longevity. This research aims to examine the additive manufacturing parameters of Poly-Ether-Ether-Ketone (PEEK), which is a thermoplastic with mechanical properties similar to osseous tissue (bone tissue). PEEK is a unique and promising material due to its biocompatibility and proficiency for use in additive manufacturing. The objective of this research is to determine the ideal set of fused deposition modeling parameters, using PEEK, which exhibits the optimal mechanical and surface qualities for use in biomedical applications aimed at tribo-corrosive environments.
A literature review was conducted to find the primary parameters to experiment within a set of value ranges for the fused deposition modeling of PEEK, which are: nozzle temperature, platform temperature, printing speed, layer height, and infill percentage. In order to efficiently test the interactions of these parameters, an L-27 Taguchi experimental design was produced: five parameters, each with three parameter levels for a total of 27 samples. Scratch tests, wear tests, and indentation tests will be repeatedly performed on the horizontally oriented samples. This process will be replicated with samples printed in a vertical orientation, where the smallest surface area is in contact with the platform. The results of the tests will be analyzed in order to sort out the parameters to use for an optimal quality 3D printed part using PEEK. Overall, advances in the additive manufacturing of composite Poly-Ether-Ether-Ketone maintain an encouraging outlook for the production of custom biomedical implants that possess properties similar to bone tissue.

Hi my name is Aditya Pulipaka and my research project is on the Design, Development, and Characterization of 3D Printed PEEK. PEEK stands for Poly Ether Ether Ketone and is a thermoplastic, which means that the material is melted by the printer and then extruded to the place that it is wanted, where It will cool and harden. This material was chosen because it is biocompatible, where we hope to apply our research to biomedical applications, where these can be utilized in place of defective bone tissue. This material was specifically chosen, as initial tests show that it has mechanical properties similar to bone tissue. Since it has the ability to be 3D printed, it can be customizable to any patient to fit individual constraints in respect to height, width, length, and density. We use a Taguchi table, which is shown on the far-right picture, that details the different variables that a 3D printer has, which includes nozzle temperature, platform temperature, printing speed, and infill percentage. The importance of this table is that it gives us 27 different combinations for samples each with different levels of all these printing properties, One of which of these samples can be seen in the picture on the lower left. These designs are made within AutoCAD and then placed into a slicer program for the printer to read. Currently we are in the testing process, where we have finished roughness testing and are currently finishing up indentation testing. From roughness testing, initial results show a correlation that samples printed with 0.1 mm layer height produce a lower value for roughness. For indentation testing, the results are still too early to find any meaningful correlation, however we are receiving a higher average modulus of elasticity in our 3D printed PEEK compared to that of manufactured PEEK. These initial results are very promising because the 3D printed sample should have some important data to report. For indentation testing, the samples have ridges which don’t allow for good data of the material so this requires polishing. The surface graphs on the top show the surface before and after polishing. Can see ridges of the surface and then after u can see a much more uniform surface finish.Once we finish the surface testing, there are multiple different options that we want to consider for future research, such as the mixed polymer version of PEEK. So we will mix PEEK and another polymer such as Hydroxyapatite to create a new polymer and hope to 3D print those samples and test. This is because Hydroxyapatite properties suggest that when mixed with PEEK, It will enhance mechanical properties in terms of strength and flexibility. So, the hope is to print another 27 samples with the Hydroxiapatite and PEEK composite and perform the same tribological and mechanical tests to compare with the PEEK results to see if there are any differences in performance. Overall, advances in 3D printing of PEEK has an encouraging outlook for the production of custom biomedical implants and we hope to fulfill the potential in this field. Thank You for listening.