Title: Additive Manufacturing of Polyamide 12 Nanocomposites- Thermal and Mechanical Effects of Varying Infill Levels

Authors: Steven D. Kim, James Grubbs, Kathrin James, Rebecca Millard, Jensen Nance, Hao Wu and Joseph H. Koo

DOI: 10.33599/nasampe/c.19.0833

Abstract: Currently, polyamide 12 (PA12) and its derivative nanocomposites are common materials used in additive manufacturing. However, the component additives for nanocomposites continue to advance and further develop, which calls for development of newer and better performing PA12 nanocomposites. In this study, 13 hybrid flame retardant nanocomposite formulations containing PA12 and varied percentages of carbon fiber (CF), thermoplastic elastomer, and flame retardant (FR), were processed through a twin-screw extruder to create 1.75mm fused filament fabrication (FFF) filaments. These filaments underwent Thermogravimetric Analysis (TGA) and Microscale Combustion Calorimetry (MCC) for screening. From the combined results of these tests, top performing formulations were selected for FFF printing for further analysis. UL 94 testing was used to determine both the flammability of each formulation in 3D form. To examine the effect of infill levels on flame retardant properties, these top performing formulations were FFF printed into UL 94 test bars at 50%, 75%, and 100% crosshatch infill levels. SEM images were taken for each formulation to analyze its char microstructure.

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Conference: CAMX 2019

Publication Date: 2019/09/23

SKU: TP19-0833

Pages: 15

Price: $30.00