Accretion for direct volumetric manufacturing via addressable resistive thermal fields

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.