Improving the accuracy and surface quality of additive manufacturing products

BACKGROUND: This paper discusses the issues of increasing the dimensional accuracy of products obtained using additive technologies. As a production method, printing with fused polymer filament through an extruder (the FFF printing technology) is considered. The main problem in the production of products using this method is the lack of a systematic understanding in terms of assignment of the process modes that ensure the required accuracy and surface quality of the resulting products. This paper proposes the approach that makes it possible to develop technological recommendations to assign printing modes that ensure the stable obtaining of the required output process parameters.

AIM: Development of methodological approach to assignment of technological modes of printing with fused polymer filament, ensuring stable values of required parameters of dimensional accuracy and quality of surface layer of products.

METHODS: The study focused on the dimensional accuracy and surface quality of printed parts. Printers that print parts using an extruder nozzle served as the primary process equipment. The primary objective of the study was to substantiate a direction for improving the accuracy and quality of the parts. The study explored ways to improve the accuracy and surface quality of the parts using the analytic hierarchy process, which allows for the evaluation of options based on their significance. The final objective of the study was to confirm the feasibility of using vibration compensation to improve the accuracy and quality of the parts. The vibrations of the printer elements were measured using an accelerometer. The surface quality of the parts was assessed using a profilograph, and their dimensions were measured using a micrometer.

RESULTS: As a result of the calculation of the comparison coefficients in the analysis of the directions of increase in dimensional accuracy and print quality of the molten polymer thread, it was found that the best combination of criteria has an option that is associated with the analysis and reduction of vibrations during printer operation. The calculation was made based on the analysis of the experience of implementing the solutions under consideration in world practice. As a result of the analysis of vibrations that occur under various technological conditions, resonance conditions were revealed. An application firmware has been developed that allows you to configure the printer drive with the ability to eliminate resonances. As a result of studies of the accuracy and quality of the surface of products obtained on the basis of eliminating resonance phenomena and without it, it was found that the first option can significantly improve the output parameters of the process. As a prospect for further research, it is advisable to carry out a theoretical generalization of the results obtained in order to extend the proposed approach to printers of other designs, thereby making it more universal.

CONCLUSION: Studies have shown that the use of a methodological approach, which consists in identifying and eliminating resonant phenomena, makes it possible to increase the dimensional accuracy and surface quality of products obtained using additive technologies.