Notch static strength of additively manufactured acrylonitrile butadiene styrene (ABS)

Abstract

The present theoretical/experimental investigation deals with the problem of performing the static assessment of notched components made of additively manufactured Acrylonitrile Butadiene Styrene (ABS). The notch strength of this 3D-printed material was investigated by testing a large number of specimens, with the experiments being run not only under tension, but also under three-point bending. The samples contained geometrical features of different sharpness and were manufactured (flat on the build plate) by changing the printing direction. Being supported by the experimental evidence, the hypothesis was formed that the mechanical response of 3D-printed ABS can be modelled effectively by treating it as a material that is linear-elastic, brittle, homogenous and isotropic. This simplifying hypothesis allowed the Theory of Critical Distances to be employed also to assess static strength of 3D-printed ABS containing geometrical features. The validation exercise based on the experimental results being generated demonstrates that this theory is highly accurate, with its use leading to predictions falling mainly within an error interval of about ±20%. This level of accuracy is certainly satisfactory especially because this static assessment methodology can be used in situations of engineering relevance by making use of the results obtained by solving standard linear-elastic Finite Element models.