Fracture behavior of additively printed ABS: Effects of print architecture and loading rate

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:212

Article

Isaac, John P.¹  Dondeti, Sivareddy¹  Tippur, Hareesh, V¹ 

[1] Auburn Univ, Dept Mech Engn, Auburn, AL 36849 USA

关键词: Additive manufacturing;    Build architecture;    Fracture mechanics;    Crack growth resistance;    Strain-rate effects;    Digital image correlation;   

DOI  :  10.1016/j.ijsolstr.2020.11.027

来源: Elsevier

【 摘 要 】

Acrylonitrile Butadiene Styrene (ABS) is an inexpensive amorphous thermoplastic used for Additive Manufacturing (AM) of engineering parts. Fused Filament Fabrication (FFF) is commonly used to 3D print ABS, and it involves layer-by-layer deposition of melted thermoplastic wire through a heated nozzle along predetermined paths. The individual layers can also be configured differently and could introduce mechanical anisotropy into the final part in terms of weak planes between individual beads and layers even when the feedstock is isotropic. In this context, this research examines the dynamic fracture behaviors of three different print architectures, namely [0 degrees/90 degrees](n), [45 degrees/-45 degrees](n) and [0 degrees/45 degrees/90 degrees/-45 degrees](n) in-plane orientations, under stress-wave loading conditions and compares the results with the quasi-static counterparts. The dynamic experiments are carried out using a modified-Hopkinson pressure bar apparatus. The full-field measurement of in-plane displacements are performed using Digital Image Correlation (DIC) and ultrahigh-speed photography of V-notched specimens subjected to stress-wave loading. A novel method of analyzing DIC data by transferring it to a finite element environment to compute the J-integral using prevailing domain integral algorithms is introduced. Distinct crack initiation and growth behaviors with different failure modes are observed in the three architectures under static and dynamic loading conditions despite the macroscale elastic isotropy. The results favor [0 degrees/45 degrees/90 degrees/-45 degrees](n) architecture due to a better crack growth behavior relative to the other two, raising the possibility of fracture performance enhancement by tailoring the build architecture. (C) 2020 Elsevier Ltd. All rights reserved.

【 授权许可】

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