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  • Fabricating polymer-matrix composite materials with aligned microfibers using ultrasound directed self-assembly and stereolithography
Title: Fabricating polymer-matrix composite materials with aligned microfibers using ultrasound directed self-assembly and stereolithography
Fabricating polymer-matrix composite materials with microfibers aligned along a user-specified direction is important to obtain specific material properties, such as anisotropic electrical and thermal conductivity and improved mechanical strength. We quantify macro- and microscale alignment of microfibers embedded in photopolymer resin, 3D-printed using ultrasound directed self-assembly (DSA) and stereolithography, as a function of three dimensionless input parameters: microfiber weight fraction, dimensionless ultrasound transducer input power, and dimensionless ultrasound transducer separation distance. We use regression analysis to determine microfiber alignment as a function of the fabrication process parameters. Microscale alignment is primarily determined by microfiber weight fraction, whereas macroscale alignment is a function of microfiber weight fraction, dimensionless ultrasound transducer separation distance, and dimensionless ultrasound transducer input power. Relating microfiber alignment to the fabrication process parameters is a crucial step towards 3D-printing composite materials with specific anisotropic material properties.  more » « less
Award ID(s):
2017588
PAR ID:
10341626
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Proc. of the American Chemical Society Spring Meeting, San Diego, CA (USA), 20-24 March 2022
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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