Fabrication of parts with heterogeneous structure using material extrusion additive manufacturing

Abstract

ABSTRACT Additive manufacturing technologies (AM) have a unique capacity for handling geometrical complexity and are, therefore, ideal for producing parts with geometrically complex form and structure. In this paper, a methodology for fabricating parts of heterogeneous internal structure by thermoplastic Material Extrusion (MEX) is proposed. Construction of the corresponding layer deposition paths is performed according to locally-defined material density, encoded in the form of a voxel part model. Specific algorithms for constructing a single layer deposition path by joining elementary deposition paths of semi-random or standard shape are developed and tested. Computational tests of the developed algorithmic procedures indicate that the associated computer processing time, is comparable to that implied by conventional slicing and path planning techniques. Results of fabrication tests employing an open-hardware MEX system further prove the feasibility of the approach.