Smart Carbon Fiber-Reinforced Polymer Composites for Damage Sensing and On-Line Structural Health Monitoring
Cláudia Lopes1,2, Andreia Araújo3, Fernando Silva3
1Physics Centre of Minho and Porto Universities (CF-UM-UP), University of Minho, 4710-057 Braga, Portugal.
Polymers
|October 16, 2024
Summary
This study explores how carbon nanomaterials like reduced graphene oxide (rGO) and carbon nanofibers (CNFs) enhance strain-sensing in epoxy nanocomposites for structural health monitoring. CNFs showed superior performance by forming new conductive pathways, enabling better damage detection in smart composites.
Area of Science:
- Materials Science
- Polymer Science
- Nanotechnology
Background:
- High electrical conductivity, piezoresistive sensitivity, and stretchability are vital for nanocomposite strain sensors in smart composites.
- Carbon fiber-reinforced polymer (CFRP) composites require effective damage sensing and on-line structural health monitoring.
Purpose of the Study:
- To investigate the influence of carbon-based nanomaterials (reduced graphene oxide and carbon nanofibers) on the strain-sensing capabilities of epoxy nanocomposites.
- To understand how geometric features and loadings of nanomaterials affect tunable strain-sensing properties.
- To evaluate the stability and reproducibility of self-sensing nanocomposites.
Main Methods:
- Synthesized epoxy-based nanocomposites with varying loadings of reduced graphene oxide (rGO) and carbon nanofibers (CNFs).
- Characterized strain-sensing behavior and sensitivity (gauge factor, GF) through mechanical testing and electrical resistance measurements.
- Assessed stability and reproducibility via cyclic stretching/relaxing tests.
- Utilized digital image correlation synchronized with electrical resistance variation to study smart CFRP composites.
Main Results:
- Distinct strain-sensing behaviors and gauge factor (GF) values were observed, dependent on nanomaterial type and loading.
- The highest GF values were achieved with 0.13 wt.% rGO.
- Nanocomposites with 0.714 wt.% CNFs demonstrated the formation of new conductive pathways between nanofibers, indicating superior performance.
- rGO-based conductive networks exhibited predominantly elastic and reversible deformation.
- Modified CFRP composites (90° orientation) incorporating CNFs showed promising results due to their ability to form new conductive pathways and penetrate between fibers.
Conclusions:
- The type and loading of carbon nanomaterials significantly tune the strain-sensing capabilities of epoxy nanocomposites.
- Carbon nanofibers offer a promising approach for developing advanced self-sensing CFRP composites due to their unique conductive network formation.
- The findings support the development of smart CFRP composites for enhanced structural health monitoring and damage detection.
