Amirkabir University of Technology Amirkabir Journal of Mechanical Engineering 2008-6032 53 12 2022 02 20 Effect of 3D-Printing and Compression Molding on Anisotropy of Acrylonitrile Butadiene Styrene Micro Specimen: A Comparative Study Based on Digital Image Correlation Effect of 3D-Printing and Compression Molding on Anisotropy of Acrylonitrile Butadiene Styrene Micro Specimen: A Comparative Study Based on Digital Image Correlation 5645 5658 4522 10.22060/mej.2021.19874.7135 FA Sina Nazari-Onlaghi School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran Alireza Sadeghi School of Mechanical Engineering, College of Engineering, University of Tehran, Iran Morad KARIMPOUR School of Mechanical Engineering, College of Engineering, University of Tehran, Tehran, Iran Hadi Mohammadi School of Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran Journal Article 2021 04 17 This paper aims to calculate and compare normal anisotropy coefficients in 3D-printed and hot-compression molded micro acrylonitrile butadiene styrene specimens. To achieve this goal, micro specimens of additively-printed and compression-molded acrylonitrile butadiene styrene were fabricated and tested using a micro-tensile testing apparatus integrated with an optical microscope while deformation of the specimens was recorded by a camera. Frames from this video were selected and strain distribution on a micron-sized area of interest was obtained using digital image correlation analysis. It was shown that there exists a close agreement between digital image correlation results and in situ optical observations. The plastic anisotropy coefficients (<em>R</em>-values) were then calculated from the surface strains as a function of the applied strain. For this purpose, a through-thickness strain component was obtained assuming plastic incompressibility condition. Results showed that both micro samples revealed an anisotropic response during plastic deformation. At low plastic strains, the printed micro specimen exhibits a more anisotropic behavior than the monolithic micro specimen. As the deformation proceeds, the normal anisotropy coefficient increases for the additively-manufactured micro specimen and decreases for the hot-pressed micro specimen.  This paper aims to calculate and compare normal anisotropy coefficients in 3D-printed and hot-compression molded micro acrylonitrile butadiene styrene specimens. To achieve this goal, micro specimens of additively-printed and compression-molded acrylonitrile butadiene styrene were fabricated and tested using a micro-tensile testing apparatus integrated with an optical microscope while deformation of the specimens was recorded by a camera. Frames from this video were selected and strain distribution on a micron-sized area of interest was obtained using digital image correlation analysis. It was shown that there exists a close agreement between digital image correlation results and in situ optical observations. The plastic anisotropy coefficients (<em>R</em>-values) were then calculated from the surface strains as a function of the applied strain. For this purpose, a through-thickness strain component was obtained assuming plastic incompressibility condition. Results showed that both micro samples revealed an anisotropic response during plastic deformation. At low plastic strains, the printed micro specimen exhibits a more anisotropic behavior than the monolithic micro specimen. As the deformation proceeds, the normal anisotropy coefficient increases for the additively-manufactured micro specimen and decreases for the hot-pressed micro specimen.  https://mej.aut.ac.ir/article_4522_f110a326be6999afdeb8e7002c0ce44d.pdf