Influence of Multi-Walled Carbon Nanotubes on Tensile Properties and Printing Quality of 3D-Printed Acrylonitrile-Butadiene-Styrene Nanocomposites

Hypothesis:

 Due to the nature of a fused deposition modeling (FDM), by which the parts are fabricated layer by layer, many defects are developed during printing of the products. Therefore, a few efficient solutions are required to minimize the defects and other shortcomings. The increase in the physical and mechanical properties of the fabricated parts using nanoparticles seems to be one of the methods.

To improve the mechanical properties of acrylonitrile-butadiene-styrene (ABS), which is one of the most common materials employed in FDM technique, various amounts (1, 3 and 5 wt%) of multi-walled carbon nanotubes (MWCNTs) were added to the matrix through a melt mixing process. The filaments containing different MWCNTs contents, required for fabricating of the samples, were then prepared by extrusion. Next, the samples were printed with the layer thicknesses of 0.05, 0.1 and 0.2 mm and raster angles of +45/-45° and 0/90°. Several experiments such as the tensile and rheological tests as well as scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations were carried out to examine the nanocomposite samples.

The SEM and TEM studies revealed that the nanoparticles were reasonably well dispersed throughout the matrix. The results of the tensile tests indicated that by addition of MWCNTs, the tensile strength and Young's modulus were increased by 21% and 103%, respectively, in comparison to those of the pristine material. It was also found that at a constant layer thickness, the maximum value of the tensile strength was obtained for the nanocomposite containing 3 wt% MWCNTs, however, the modulus progressively increased with the increase of the nanoparticles content. In addition, the change in raster angle showed no significant effect on the tensile properties, and the increasing of the layer thickness had an adverse effect on the properties for all the materials examined.