Failure Analysis and Mechanical Characterization of 3D Printed ABS With Respect to Layer Thickness and Orientation

In contrast to conventional subtractive manufacturing methods which involve removing material to reach the desired shape, additive manufacturing is the technology of making objects directly from a computer-aided design model by adding a layer of material at a time. In this study, a comprehensive effort was undertaken to represent the strength of a 3D printed object as a function of layer thickness by investigating the correlation between the mechanical properties of parts manufactured out of acrylonitrile butadiene styrene (ABS) using fused deposition modeling and layer thickness and orientation. Furthermore, a case study on a typical support frame is done to generalize the findings of the extensive experimental work done on tensile samples. Finally, fractography was performed on tensile samples via a scanning digital microscope to determine the effects of layer thickness on failure modes. Statistical analyses proved that layer thickness and raster orientation have significant effect on the mechanical properties. Tensile test results showed that samples printed with 0.2 mm layer thickness exhibit higher elastic modulus and ultimate strength compared with 0.4 mm layer thickness. These results have direct influence on decision making and future use of 3D printing and functional load bearing parts. © 2016, ASM International.