Author/Authors :
Zhao, Haibo North Carolina State University - Department of Mechanical and Aerospace Engineering, USA , Zhang, Yingying Center for Integrated Nanotechnologies - Los Alamos National Laboratory, USA , Bradford, Philip D. North Carolina State University - Department of Material Science and Engineering, USA , Zhou, Qian North Carolina State University - Department of Chemical and Biomolecular Engineering, USA , Jia, Quanxi Center for Integrated Nanotechnologies - Los Alamos National Laboratory, USA , Yuan, Fuh-Gwo North Carolina State University - Department of Mechanical and Aerospace Engineering, USA , Zhu, Yuntian North Carolina State University - Department of Material Science and Engineering, USA
Abstract :
Carbon nanotube (CNT) based sensors are often fabricated by dispersing CNTs into different types of polymer. In this paper, a prototype carbon nanotube (CNT) yarn strain sensor with excellent repeatability and stability for in situ structural health monitoring was developed. The CNT yarn was spun directly from CNT arrays, and its electrical resistance increased linearly with tensile strain, making it an ideal strain sensor. It showed consistent piezoresistive behavior under repetitive straining and unloading, and good resistance stability at temperatures ranging from 77 to 373 K. The sensors can be easily embedded into composite structures with minimal invasiveness and weight penalty. We have also demonstrated their ability to monitor crack initiation and propagation.
