Effect of raster angle on mechanical properties of 3D printed short carbon fiber reinforced acrylonitrile butadiene styrene

The most common additive manufacturing technique fused filament fabrication (FFF) suffers from inter-bead porosity that reduces mechanical properties. Inter-bead pores follow the raster angle, which causes anisotropic mechanical properties. Yet, the effects of raster angle on the mechanical behavior of short-carbon-fiberreinforced (SCFR) thermoplastics are unclear. In this study, we performed tensile, flexural, and fracture toughness tests on SCFR acrylonitrile butadiene styrene (ABS). Raster angles of 0 degrees, 15 degrees, 30 degrees, 45 degrees, 60 degrees, 75 degrees, and 90 degrees were investigated. Tensile strength and elastic modulus decreased by 22-35% for a change from 0 degrees to 15 degrees. Flexural strength and modulus were less sensitive to raster angle. Flexural strengths were at least 50% more than tensile strength for the same raster angle. Whereas flexural modulus is at least 15% less than elastic modulus. Fracture toughness showed a non-linear relationship with the raster angle. Maximum fracture toughness was observed at 0 degrees and 60 degrees rasters. Crack deflection was observed as the toughening mechanism.

Automated summary

This study investigated the mechanical behavior of short-carbon-fiber-reinforced thermoplastics at different raster angles. The results showed that tensile strength and elastic modulus decreased with the change in raster angle, while flexural strength and modulus were less affected. Additionally, there was a non-linear relationship between fracture toughness and raster angle, with the maximum toughness observed at 0 degrees and 60 degrees.