Accretion for direct volumetric manufacturing via addressable resistive thermal fields.

Abstract The vast majority of additive manufacturing methods rely on an ultra-serialized approach for building parts. Often described as "layer-by-layer," in reality, these are hierarchically serial, point-by-point, path-by-path and layer-by-layer approaches. The multi-scale stratification of mass and accompanying complex thermal histories introduced by thermally-based hierarchical processes such as selective laser melting (SLM), fused deposition modeling (FDM), and direct metal laser deposition (DMLS), give rise to a number of limitations in terms of build times with respect to part size and scale, as well as structural performance due to process-induced inhomogeneities. This work proposes a new methodology that has the potential for addressing these drawbacks by implementing a truly volumetric approach to additive manufacturing of fiber-reinforced-like composite objects. That is, instead of building parts a single point at a time in a hierarchical manner, by spatially controlling the energy distribution within a three-dimensional build domain, one can build parts from large constituent volumes, in parallel, by addressable, resistive heating. The work presented herein consists of a theoretical treatment of the underlying physics, process planning via the solution of an inverse problem for implementing the proper control, and, finally, a preliminary demonstration of the process. Highlights • Accretive, volumetric additive manufacturing (AM) enables significant reduction in build time and build time scaling (L3 → L). • Enabled by three-dimensional control of temperature distribution of build volume via addressable resistive wire array. • Process results in mechanically-stabilized composite material response. • Process requires no moving parts to operate (completely "solid-state"). • Process allows for in-situ postprocessing. [ABSTRACT FROM AUTHOR]