3D PRINTED SMART MOLD FOR SAND CASTING: Monitoring Binder Curing

3D printing of sacrificial molds and cores involves binder jetting in which a binder is selectively inkjetted into a bed of sand premixed with an acid to provide the two-part furan curing reaction. After one layer of binder is jetted, the bed descends by a layer thickness (typically 250 microns) and a new layer of unbound sand is deposited uniformly across the bed and the process repeats. Interrupting the process and gaining access to the bed is possible with an ExOne SMAX printer and the capability to integrate components, and subsequently to continue the process to construct smart molds is now possible and relatively unexplored. Here, Bryant et al investigate the insertion of fully embedded sensors into 3D printed sand structures during process interruptions in the binder jetting of Furan-based sand molds.