Deformation constrained support-structure optimization for laser powder bed fusion

Abstract

Support structures act as primary conduits for heat flow in laser powder bed fusion (LPBF). Frame supports, as opposed to block-type supports, have proven to be a good choice for LPBF, with no metal powder entrapment and ease of removal. In this paper, we use a multi-load formulation, where different loads at different instances of time are used for frame support optimization, to constrain the structural deformation of the part during printing. Parts and supports are analyzed in tandem at the end of each layer build, to account for the role of support stiffness in the overall part deformation. The proposed framework prevents recoater collision, and controls the geometric accuracy of the part, by optimizing the size of frame supports. Numerical results for the optimal volume of manufacturable frame support are reported for geometries with varying overhang characteristics.