Low‐Roughness 3D‐Printed Surfaces by Ironing for the Integration with Printed Electronics

Abstract

The roughness of 3D‐printed surfaces poses a challenge when integrating fused filament fabrication (FFF) printing with printed electronics, leading to inconsistencies and breaks in the circuit traces. To improve the surface roughness, we propose an ironing toolpath. The ironing toolpath involves the hot nozzle going over the printed surface with finer line spacing, remelting the surface to fill gaps, and creating a smooth finish. For further optimization, various ironing parameters are investigated including flow, speed, line spacing, and temperature. A wide range of materials is tested, including commonly used low‐temperature filaments (PLA, PETG, ABS) and high‐temperature filaments (PSU, PEI, PEEK) suitable for integration with printed electronics and medical applications. To collect the extensive datasets an automated measurement system is deployed. With this method, surface roughness reductions of up to 96.6% are achieved and significant trends are identified. Lastly, the integration of 3D printing with electronics is demonstrated by printing a high‐resolution strain gauge structure on top of an ironed surface and embedding it into fully printed tweezers which could be used in medical robotics. The insights on ironing extend beyond electronics and can also be valuable in other areas where low surface roughness of FFF‐printed parts is required.This article is protected by copyright. All rights reserved.