Discrete in-situ consolidation of additively manufactured continuous fiber-reinforced polymer composites

Discrete in-situ consolidation (DISC) of continuous fiber-reinforced polymer composites deposited by fused filament fabrication (FFF) is demonstrated to significantly reduce porosity and increase mechanical performance. In DISC, a narrow, heated tool applies a pressure to consolidate pre-deposited beads individually. By alternating between material deposition and DISC, well-consolidated material can be built up layer-by-layer. Material samples produced using FFF and DISC are benchmarked against those prepared via FFF alone and FFF combined with compression molding. Void contents were found to decrease significantly from 40.4% to 4.3% when compared to parts produced by FFF alone, and short-beam strength was shown to be on the order of 70% of what could be achieved via compression molding. To demonstrate the suitability of DISC for manufacturing geometrically complex forms, a rotary axis additive manufacturing system was developed and used to produce cylindrical parts, including lattice shell structures and multi-turn wave springs.

Automated summary

It is shown that discrete in-situ consolidation (DISC) can significantly reduce porosity and increase mechanical performance in continuous fiber-reinforced polymer composites deposited by fused filament fabrication (FFF). By alternating between material deposition and DISC, well-consolidated material can be built up layer-by-layer. DISC technology is also demonstrated to be suitable for manufacturing geometrically complex forms.