Thermally Switchable Build Table by Mechanical Interlocking for Additive Manufacturing

This work presents a method for achieving a thermally switchable bond on a build table for Additive Manufacturing using mechanically interlocking features. Removal of parts from the build table remains a challenge. Furthermore, the residual stress that develops as multiple layers are deposited in an ambient environment can lead to the part detaching from the build table if bonding is insufficient. To achieve ample part to build table bonding, undercut features are machined into a metal build table onto which the molten polymer is extruded. Upon solidification, a mechanical bond is formed. The part can then be easily removed through rapid heating of the undercut features, resulting in a loss of mechanical bonding. We present results from our lab-scale setup allowing fundamental studies of the core physics. The method can easily be scaled larger or smaller by proportionally sizing the undercut features to the plastic extrusion bead size and parameters.