Novel experimental and multiscale study of additively manufactured ABS-carbon nanotubes nanocomposites

Abstract

The additively manufactured (3D printed) nanocomposite parts demonstrate challenges in terms of poor dispersion and agglomeration. To investigate such structures advanced computational models are required to capture smaller-scale phenomena. This study proposes a novel three-scale computational model for calculating the mechanical properties of 3D-printed nanocomposites. The study also proposes a novel water-quenching experimental technique to prepare in situ nanocomposite sheets during nanocomposite filament manufacturing. The computational model integrates Halpin Tsai and Eshelby Mori Tanaka model at the microscale integrated with the asymptotic homogenization model at meso and macro scales to calculate the effective elastic modulus of 3D printed nanocomposite parts. The experimental characterization was performed by using the water quenching method to prepare 0.5 wt%, 1 wt%, 1.5 wt%, and 2 wt% multiwalled carbon nanotube (MWCNT)-ABS nanocomposite filaments, 3D printed parts, and finally tensile testing them. Furthermore, morphological analysis was conducted to study the dispersion and agglomeration effect and effectiveness of the proposed new method. Finally, the computational results were compared with experimental results to validate the model. Elastic modulus showed an increase of 2.79 %, 6.5 %, 9.6 %, and 12.6 % for 0.5 wt%, 1 wt%, 1.5 wt%, and 2.0 wt% CNT-ABS filaments. Similarly, for 2 wt% CNT-ABS and 0.5 wt% CNT-ABS 3D printed parts, a 20.4 % and 10.3 % increase was reported. In comparison with literature reporting a decrease of 3.35 % and an increase of 1 % in the elastic modulus for 1 wt% and 2 wt% CNT-ABS filaments, the present method reported an increase of 6.54 % and 12.6 % respectively. Moreover, for 1 wt% 3D printed part, an increase of 14.2 % compared to 1 % in the literature is reported.