Investigation of the effect of three-point bending testing parameters on the behavior of 3D printed sand

Abstract

3D sand mold printing allows rapid and direct fabrication of complex-shaped molds and cores that helps to overcome the limitations of conventional casting. The manufactured molds and cores, having complex geometries, are subjected to severe thermomechanical loads during casting and thus must have sufficient rigidity to meet the technical requirements. Therefore, a mastery of their behavior and intrinsic sand properties becomes essential for a better dimensioning of molds and cores but also the simulation of casting processes. The bending is the most critical load type, for sand cores under casting conditions, and therefore needs to be characterized. This study proposes to investigate the effect of testing parameters, which are span-to-thickness and strain rate, on the three-point bending behavior of printed sand. The results showed that the elastic modulus increases with the rise of the span-to-thickness parameter and is not affected by the strain rate. The bending strength, for its part, is only affected by strain rate. The test results and DIC measurement made it possible to give recommendation for the optimal testing parameters.