Title: ENHANCING BUILD DIRECTION TENSILE STRENGTH OF 3D PRINTED CARBON FIBER REINFORCED NYLON 6 COMPOSITE

Authors: Laksh Thanki, Rampal Singh, Keyur Joshi, Arijit Ganguli, Vishal Nirgude, Raj Das, Shuja Ahmed

DOI: https://doi.org/10.33599/GL.2026.INCOMAT.TP26-0007

Abstract: This study investigates the mechanical anisotropy of Fused Deposition Modeling (FDM) parts, specifically focussing on enhancing the build direction tensile strength of the Short Carbon Fiber Reinforced Nylon 6 (CF-PA6) composites. While FDM components printed horizontally benefited from fiber matrix alignment along loading direction, printed horizontally and on-edge benefited from fiber-matrix alignment along the loading direction, vertical specimen often exhibited a low tensile strength due to reliance on polymer to polymer interlayer bonding. To address this, a paired printing strategy was employed to manipulate the layer cooling time by varying the separation distance between two specimens under both active (fan on) and passive cooling (fan off) conditions. The experimental results identified a critical trade-off. The study established an optimum separation distance of 30 mm for both strategies. At separation distances below 30 mm, active cooling resulted in over-quenching and amorphous structure formation, while passive cooling caused heat accumulation and moisture-induced void growth. Conversely, distances above 30 mm led to cold interface failure due to inhibited molecular reptation. Notably passive cooling strategy at 30 mm yielded the highest Ultimate Tensile Strength (UTS) of 29.77 ± 2.18 MPa, which is approximately 30% higher than the best result achieved with the active cooling. These findings demonstrate that controlling the cooling rate via passive strategies combined with optimized layer times significantly improves the z-strength of hygroscopic, semi-crystalline CF-PA6 composites

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Conference: INCOMAT 2026

Publication Date: 2026/03/13

SKU: INCOMAT.TP26-0007

Pages: 13

Price: $26.00