Scaling up the 3D printing of surgical guides: repeatability and energy efficiency

Purpose: This paper aims to investigate the repeatability of the Stereolithography (SLA) process and to provide reliable guidelines to minimize energy consumption without sacrificing part quality. To tackle these aims, an extensive experimental campaign has been conceived: two different machines (of the same model) have been operated in different production environment, specimens and parts with different orientations have been manufactured. Design/methodology/approach: A two-step experimental campaign has been carried out. In the first stage, surgical guides were printed with different positions and orientations with respect to the printing plate to investigate the link between energy consumption and printing configuration. In the second stage, the repeatability of the process has been studied, dog bone specimens, accuracy cubes and surgical guides have been printed with two printers operating in two different production environments. Energy consumption, mechanical properties and dimensional accuracy have been measured as reference output to assess the repeatability and the energy consumption of the process. Findings: Repeatability was found to be quite stable and reliable by using the same machine in the same production environment. In particular, by varying machine and production environments, variability was found to be low in dimensional accuracy and high for mechanical properties since they are affected by resin temperature, room temperature and the electrical system of the building. Thus, in this study, it was found that the production environment plays a non-negligible role in the output of the manufacturing processes, and it is necessary to be considered especially for scaling up 3D printing. Originality/value: Additive manufacturing (AM) parts production for biomedicine represents a prosumer-oriented phenomenon. This market relies on the repeatability of the printing process which is where the AM processes usually fall short. Moreover, this increasing demand needs to be properly managed to pursue sustainable development, thus responsible energy consumption is mandatory. Nevertheless, energy consumption to manufacture 3D printed parts on a large scale represents a non-negligible aspect that still has not been well considered in the literature. The joint investigation of energy consumption, mechanical properties and dimensional accuracy to evaluate the repeatability and energy efficiency of SLA parts represents the novelty of this study.