3D-printed PEEK-carbon fiber (CF) composites: Structure and thermal properties. (18th August 2018)

• Record Type: Journal Article
• Authors: Stepashkin, А.А.; Chukov, D.I.; Senatov, F.S.; Salimon, A.I.; Korsunsky, A.M.; Kaloshkin, S.D.
• Is Part Of: Composites science and technology. Volume 164(2018)
• Page Start: 319
• Page End: 326
• Publication Date: 2018-08-18
• Subjects: A. Carbon fiber -- A. Polymer-matrix composites (PMCs) -- B. Thermal properties -- D. Thermal analysis -- E. Lay-up (manual/automated); Composite materials -- Periodicals; Composite materials; Fibrous composites; Periodicals; 620.118
• DOI: 10.1016/j.compscitech.2018.05.032
• Languages: English
• ISSNs: 0266-3538

Abstract

Abstract: CF-PEEK composites were manufactured by 3D-printing using a novel FDM methodology and customized printer and were compared with their cast counterparts. The characterization of composite thermal properties in the range 25–300 °C revealed that 3D-printed CF-PEEK composites manifest 25–30% lower thermal conductivity than cast composites. Short carbon fibers used for reinforcement showed orientation along the polymer flow both in cast and 3-D printed samples causing the anisotropy of thermal properties. The hierarchical nature of 3DP CF-PEEK porosity was observed by SEM imaging, which allowed the identification of large scale inter-layer gaps and cracks, and fine scale intra-layer defects that are likely to be induced by the thermal and mechanical gradients within the deposit that arise during fabrication. Purposeful lay-up of long continuous carbon yarns during 3D-printing opens a way to fabricate tailored mechanical parts with desired anisotropy of properties. Highlights: Successful 3D printing of continuous Carbon Fiber-reinforced PEEK matrix composites is reported. Porosity caused by 3D printing reduces density and thermal conductivity compared to cast composites. Large pores at the interfaces of deposited layers lead to damage localization and multiple crack formation under load. Fine imperfections within individual layers caused by process-induced temperature gradients give rise to small-scale cracks. Hierarchical porosity induces thermal conductivity anisotropy of 3DP CF-PEEK structures compared to their cast counterparts.