Topology Optimization for Additive Manufacturing: A Front Propagation-based Approach

Emiel van de Ven (PhD candidate), Can Ayas, Matthijs Langelaar, and Fred van Keulen (supervisor) 

Most additive manufacturing processes, such as selective laser melting (SLM), fused deposition melting and stereo lithography, exhibit an overhang limitation. This is caused by the fact that each layer needs a certain amount of mechanical support and/or thermal conduction from the previously built layer, which limits the distance that a layer can extend unsupported over the layer underneath. Manufacturability is thus controlled by the angle between a down-facing surface and the base plate, the overhang angle. The minimum overhang angle, αoh, is the smallest manufacturable overhang.

Schematic illustration of the critical overhang angle and a failure in printing process when critical overhang angle is violated.