Experimental characterization and validation by FEM analyses of a 3D-printed support

Devices for training of healthcare specialists are widespread applications of 3D printing. BES TEST (TM) is an innovative test for the diagnosis of osteoporosis and similar bone diseases, based on mechanical simulations performed on a virtual biopsy of the patient's fingers, obtained by radiograms. Operator training is performed on a phantom hand, which is held in place by a specifically-designed support, which was 3D printed using stereolithography (SLA) with Formlabs Tough V5 (TM) resin. Our aim is twofold: (1) perform a mechanical characterization of the resin and (2) verify that the obtained material characteristics can be used for the design of 3D-printed parts, in particular the phantom hand support. Tensile tests were performed following ISO-527. FEM analyses were carried out on the support CAD model adopting the experimentally-obtained material properties. The calculated displacements were compared with those measured experimentally on the prototype, which was manufactured using the same 3D printing and post-curing parameters as the tensile samples. FEM and experimental results were in very good agreement (error < 5.5%): this confirms that, when studying the mechanical performance of SLA 3D-printed parts, it is good practice to characterize the resin using the same printing and post-curing parameters as the final part.