Characterizing short-fiber-reinforced composites produced using additive manufacturing

• Published in: Advanced manufacturing. Polymer & composites science Vol. 3; no. 3; pp. 81 - 91
• Main Authors: Ivey, Marcus, Melenka, Garrett W., Carey, Jason. P., Ayranci, Cagri
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 03.07.2017; Taylor & Francis Ltd; Taylor & Francis Group
• Subjects: Additive manufacturing; Annealing; Carbon fibers; Crystal structure; Crystallinity; Differential scanning calorimetry (DSC); Extrusion; Fiber composites; Filaments; Fillers; Material extrusion additive manufacturing; Mechanical properties; Mechanical testing; Modulus of elasticity; Optical extensometry; Polylactic acid; Short-fiber composite; Statistical methods; Tensile properties; Three dimensional printing
• ISSN: 2055-0340; 2055-0359
• DOI: 10.1080/20550340.2017.1341125

Material extrusion additive manufacturing (MEAM), a sub-branch of three-dimensional (3D) printing is growing in popularity. Test specimens were 3D-printed using commercial polylactic acid (PLA) filament, and PLA filament reinforced with short-carbon fibers (PLA/CF). As-printed specimens and specimens that were annealed at three different temperatures, then subjected to tensile testing. The internal microstructures of the samples were also examined. The effects of the short-carbon fiber fillers on the mechanical properties of 3D-printed PLA were investigated, and the effects of the annealing process on polymer crystallinity and mechanical properties. The annealing process was shown to increase the crystallinity of both sample groups, though no statistically significant effect of annealing on mechanical properties was observed. The tensile properties of the PLA and PLA/CF filaments showed that the addition of carbon fibers to the PLA filament led to a significant increase in elastic modulus of the MEAM samples.