Fabrication of Gradient Density Components Through Extrusion-Based Additive Manufacturing

Due to its sequential and localized manner of material addition, additive manufacturing (AM) is very suitable to fabricate components with gradient density. This study attempts to generate components with gradient density through extrusion-based AM process using Hilbert area-filling curve. Four square samples having different infill density were fabricated by fused filament fabrication. A silicon membrane covering the various regions of the pattern was applied on one side of the surface, which helps in the experimental measurement when subjected to loading. Further, a demonstration case study of a shoe sole was taken to generate and fabricate with the gradient density based on the foot pressure data. Deflections of the membrane at different locations when subjected to uniform loading were measured. The behavior of the fabricated sample matched with the desired foot pressure data, thus validating the approach. This study can provide the basic framework to generate a gradient density component.