Balance between bonding and deposition during fused deposition modeling of polycarbonate and acrylonitrile-butadiene-styrene composites

To investigate the mechanical properties of fused deposition modeling (FDM) parts, a compatibilizer and nanoparticles were used as additions in Polycarbonate and Acrylonitrile-Butadiene-Styrene (PC/ABS) blends, and four PC/ABS composites were used to fabricate the FDM samples in this study. Two simplified deposition modes of the FDM process were proposed and used to investigate the bonding effect and deposition effect. The bonding effects of the four materials were first investigated using model I of the FDM process. Then, a linear relationship between the bonding strength and the porosity was found, and the optimal processing conditions that produced the best bonding strength were determined. These optimal processing conditions were then used in mode II of the FDM process to fabricate four samples. The mechanical properties and structural characterizations of these samples were studied using tensile tests, dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM). One interesting phenomenon observed from the tensile tests was that the necking of the PC/ABS FDM sample can spread throughout the total gauge length and measure more than 100% of the strain when the compatibilizer and the nanoparticles were added, which can be attributed to a balance between bonding properties and ductility. The results verify the applicability of PC/ABC composites to FDM technology and suggest that compatibilizers and nanoparticles are suitable candidates to improve the bonding strength and the deposition effect of PC/ABS FDM parts. In conclusion, the balance between bonding properties and ductility is key to improving the tensile behaviors of PC/ABS FDM parts by adjusting the compatibility and porosity of blended PC/ABS samples.