Electric field assisted fused deposition modeling for improving nozzle cleanliness

Abstract

Fused deposition modeling (FDM) is one of the most popular additive manufacturing processes. It has been utilized in a variety of research fields and applications. However, little attention has been paid to the nozzle cleanliness issue in the FDM process. Debris of extruded polymer materials can easily build up on the nozzle surface in the printing process and the accumulated debris typically falls on the actual printing area, which degrades the quality of printed parts. This paper innovated an approach to reduce polymer debris build-up on the nozzle during the FDM printing process. An electric-field-assisted FDM (E-FDM) process was proposed to improve the nozzle cleanliness. E-FDM utilizes a high voltage power supply to generate an electrostatic force between the nozzle and build plate, which has great potential to avoid accumulations of melted thermoplastic materials on FDM nozzles. To verify the effectiveness of the E-FDM process, both E-FDM and conventional FDM processes were used to print test specimens for certain durations of time. Debris built up on the nozzle surface was characterized by 3D scanning to quantify the volume changes of the nozzle. The E-FDM printing reduced debris accumulation by 47% after ∼5 hours of printing and over 80% after ∼15 hours of printing as compared to the conventional FDM process. The results demonstrated the effectiveness of the electric-field-assisted FDM process in reducing the nozzle debris built up on the nozzle surface.