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Title: Laser induced graphene in fiberglass-reinforced composites for strain and damage sensing
Structural health monitoring of fiber-reinforced composite materials is of critical importance due to their use in challenging structural applications where low density is required and the designs typically use a low factor of safety. In order to reduce the need for external sensors to monitor composite structures, recent attention has turned to multifunctional materials with integrated sensing capabilities. This work use laser induced graphene (LIG) to create multifunctional structure with embedded piezoresistivity for the simultaneous and in-situ monitoring of both strain and damage in fiberglass-reinforced composites. The LIG layers are integrated dur-ing the fabrication process through transfer printing to the surface of the prepreg before being laid up into the ply stack, and are thus located in the interlaminar region of the fiberglass-reinforced composite. The methods used in this work are simple and require no treatment or modification to the commercial fiberglass prepreg prior to LIG transfer printing which is promising for industrial scale use. The performance of the piezoresistive interlayer in monitoring both strain and damage in-situ are demonstrated via three-point bend and tensile testing. Addi-tionally, the interlaminar properties of the fiberglass composites were observed to be largely maintained with the LIG present in the interlaminar region of the more » composite, while the damping properties were found to be improved. This work therefore introduces a novel multifunctional material with high damping and fully inte-grated sensing capabilities through a cost-effective and scalable process. « less
Authors:
Award ID(s):
1762369
Publication Date:
NSF-PAR ID:
10191089
Journal Name:
Composites science and technology
Volume:
199
Page Range or eLocation-ID:
108367
ISSN:
0266-3538
Sponsoring Org:
National Science Foundation
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