Authors: X. Li and C. Levy
Affilation: Florida International University, United States
Pages: 256 - 259
Keywords: multiwalled carbon nanotube, resistance, strain sensor, vibration control
We have employed pure multi-walled carbon nanotube (MWCNT) films as strain sensors for structural vibration control. The MWCNT films were prepared by solution/filtration method and were bonded directly onto aluminum specimens by nonconductive adhesives. Conventional strain gauges were also bonded to the structure on the opposite side for comparison. The specimens then underwent uniaxial tensile loading-unloading cycle to evaluate them as strain sensors. A simple and reliable technique was developed to assure good electrical contact between carbon nanotube films and the wires. Two-point probe method and Wheatstone bridge were used to convert the resistance changes of MWCNT to voltage. Results indicated the voltage output was proportional to the applied strain. The temperature effect on the resistance was measured and the MWCNT film resistance was found to be temperature-independent. Film dimensions also affected the strain sensing capability of the MWCNT and an optimal shape was determined. Our results indicated that MWCNT film has the potential as strain sensors for structural health monitoring and structural vibration control.