Curing parameters to improve the mechanical properties of stereolithographic printed specimens
Abstract
Purpose
This paper presents findings from a study examining curing procedures to improve the compressive strength and hardness properties of specimens while maintaining surface quality. All specimens were created from a standard grey, acrylic-based photopolymer and fabricated using stereolithography technology. This paper aims to investigate the effects of printing layer thickness and print orientation on specimen compressive strength, as well as the effects of thermal and light curing methods. In addition, the post-print curing depth was investigated.
Design/methodology/approach
The effects of layer thickness and print orientation were investigated on 10 × 20 mm cylinders by determining the ultimate compressive strength once cured. The compressive strength of cylinders subjected to varying thermal and light settings was also investigated to determine the optimal curing settings. The effective depth of curing was investigated on a 25.4-mm cuboidal specimen, which received both thermal and light curing.
Findings
To achieve the highest compressive strength, specimens shall be printed with the minimal layer thickness of 25 µm. Increasing temperatures up to 60° C during curing provided a 0.75-MPa increase in compressive strength per degree Celsius. However, increasing temperatures above 60° C only provided a 0.15-MPa increase in compressive strength per degree Celsius. Furthermore, curing temperatures above 110° C resulted in degraded surface quality noted by defects at the layer laminations. Specimens required a minimum light curing exposure time of four hours to reach the maximum cure at which point any increase in exposure time provided no substantial increase in compressive strength.
Originality/value
This study provides recommendations for printing parameters and curing methods to achieve the optimum mechanical properties of cured stereolithography specimens.
Keywords
Acknowledgements
This material is based upon work supported by the National Science Foundation under Grant No. 1463516. Any opinions, findings and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. The authors also wish to acknowledge the support provided by the Department of Civil Engineering at the University of Arkansas.
Citation
Watters, M.P. and Bernhardt, M.L. (2018), "Curing parameters to improve the mechanical properties of stereolithographic printed specimens", Rapid Prototyping Journal, Vol. 24 No. 1, pp. 46-51. https://doi.org/10.1108/RPJ-11-2016-0180
Publisher
:Emerald Publishing Limited
Copyright © 2018, Emerald Publishing Limited