Computational design strategy to improve RF heating uniformity
ISSN: 1355-2546
Article publication date: 8 March 2022
Issue publication date: 2 August 2022
Abstract
Purpose
Recent work has demonstrated the possibility of selectively sintering polymer powders with radio frequency (RF) radiation as a means of rapid, volumetric additive manufacturing. Although RF radiation can be used as a volumetric energy source, non-uniform heating resulting from the sample geometry and electrode configuration can lead to adverse effects in RF-treated samples. This paper aims to address these heating uniformity issues by implementing a computational design strategy for doped polymer powder beds to improve the RF heating uniformity.
Design/methodology/approach
Two approaches for improving the RF heating uniformity are presented with the goal of developing an RF-assisted additive manufacturing process. Both techniques use COMSOL Multiphysics® to predict the temperature rise during simulated RF exposure for different geometries. The effectiveness of each approach is evaluated by calculating the uniformity index, which provides an objective metric for comparing the heating uniformity between simulations. The first method implements an iterative heuristic tuning strategy to functionally grade the electrical conductivity within the sample. The second method involves reorienting the electrodes during the heating stage such that the electric field is applied in two directions.
Findings
Both approaches are shown to improve the heating uniformity and predicted part geometry for several test cases when applied independently. However, the greatest improvement in heating uniformity is demonstrated by combining the approaches and using multiple electrode orientations while functionally grading the samples.
Originality/value
This work presents an innovative approach for overcoming RF heating uniformity issues to improve the resulting part geometry in an RF-assisted, volumetric additive manufacturing method.
Keywords
Acknowledgements
This material is based on work supported by the National Science Foundation under Grant No. CMMI-1728015. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation.
Citation
Allison, J., Pearce, J., Beaman, J. and Seepersad, C. (2022), "Computational design strategy to improve RF heating uniformity", Rapid Prototyping Journal, Vol. 28 No. 8, pp. 1476-1491. https://doi.org/10.1108/RPJ-08-2021-0193
Publisher
:Emerald Publishing Limited
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