Thermochromic Polymer Film Sensors for Detection of Incipient Thermal Damage in Carbon Fiber–Epoxy Composites
Carbon fiber–epoxy composites have become prevalent in the aerospace industry where mechanical properties and light weight are at a premium. The significant non-destructive evaluation challenges of composites require new solutions, especially in detecting early-stage, or incipient, thermal...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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MDPI AG
2018-04-01
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| Series: | Sensors |
| Subjects: | |
| Online Access: | http://www.mdpi.com/1424-8220/18/5/1362 |
| _version_ | 1798027086184579072 |
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| author | Ryan Toivola Sei-Hum Jang Shawn Baker Alex K. -Y. Jen Brian D. Flinn |
| author_facet | Ryan Toivola Sei-Hum Jang Shawn Baker Alex K. -Y. Jen Brian D. Flinn |
| author_sort | Ryan Toivola |
| collection | DOAJ |
| description | Carbon fiber–epoxy composites have become prevalent in the aerospace industry where mechanical properties and light weight are at a premium. The significant non-destructive evaluation challenges of composites require new solutions, especially in detecting early-stage, or incipient, thermal damage. The initial stages of thermal damage are chemical rather than physical, and can cause significant reduction in mechanical properties well before physical damage becomes detectable in ultrasonic testing. Thermochromic fluorescent probe molecules have the potential to sense incipient thermal damage more accurately than traditional inspection methods. We have designed a molecule which transitions from a colorless, non-fluorescent state to a colorful, highly fluorescent state when exposed to temperature–time combinations that can cause damage in composites. Moreover, this molecule can be dispersed in a polymer film and attached to composite parts as a removable sensor. This work presents an evaluation of the sensor performance of this thermochromic film in comparison to ultrasonic C-scan as a method to detect incipient thermal damage in one of the most widely used carbon fiber–epoxy composite systems. Composite samples exposed to varying thermal exposures were used to evaluate the fluorescent thermal sensor films, and the results are compared to the results of ultrasonic imaging and short-beam shear tests for interlaminar shear strength. |
| first_indexed | 2024-04-11T18:45:45Z |
| format | Article |
| id | doaj.art-e401ac554f0d4344905186847d63b213 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T18:45:45Z |
| publishDate | 2018-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-e401ac554f0d4344905186847d63b2132022-12-22T04:08:50ZengMDPI AGSensors1424-82202018-04-01185136210.3390/s18051362s18051362Thermochromic Polymer Film Sensors for Detection of Incipient Thermal Damage in Carbon Fiber–Epoxy CompositesRyan Toivola0Sei-Hum Jang1Shawn Baker2Alex K. -Y. Jen3Brian D. Flinn4Department of Materials Science & Engineering, University of Washington, Seattle, WA 98195, USADepartment of Materials Science & Engineering, University of Washington, Seattle, WA 98195, USADepartment of Materials Science & Engineering, University of Washington, Seattle, WA 98195, USADepartment of Materials Science & Engineering, University of Washington, Seattle, WA 98195, USADepartment of Materials Science & Engineering, University of Washington, Seattle, WA 98195, USACarbon fiber–epoxy composites have become prevalent in the aerospace industry where mechanical properties and light weight are at a premium. The significant non-destructive evaluation challenges of composites require new solutions, especially in detecting early-stage, or incipient, thermal damage. The initial stages of thermal damage are chemical rather than physical, and can cause significant reduction in mechanical properties well before physical damage becomes detectable in ultrasonic testing. Thermochromic fluorescent probe molecules have the potential to sense incipient thermal damage more accurately than traditional inspection methods. We have designed a molecule which transitions from a colorless, non-fluorescent state to a colorful, highly fluorescent state when exposed to temperature–time combinations that can cause damage in composites. Moreover, this molecule can be dispersed in a polymer film and attached to composite parts as a removable sensor. This work presents an evaluation of the sensor performance of this thermochromic film in comparison to ultrasonic C-scan as a method to detect incipient thermal damage in one of the most widely used carbon fiber–epoxy composite systems. Composite samples exposed to varying thermal exposures were used to evaluate the fluorescent thermal sensor films, and the results are compared to the results of ultrasonic imaging and short-beam shear tests for interlaminar shear strength.http://www.mdpi.com/1424-8220/18/5/1362thermochromismthermal damage detectionepoxy-matrix compositesfluorescence |
| spellingShingle | Ryan Toivola Sei-Hum Jang Shawn Baker Alex K. -Y. Jen Brian D. Flinn Thermochromic Polymer Film Sensors for Detection of Incipient Thermal Damage in Carbon Fiber–Epoxy Composites Sensors thermochromism thermal damage detection epoxy-matrix composites fluorescence |
| title | Thermochromic Polymer Film Sensors for Detection of Incipient Thermal Damage in Carbon Fiber–Epoxy Composites |
| title_full | Thermochromic Polymer Film Sensors for Detection of Incipient Thermal Damage in Carbon Fiber–Epoxy Composites |
| title_fullStr | Thermochromic Polymer Film Sensors for Detection of Incipient Thermal Damage in Carbon Fiber–Epoxy Composites |
| title_full_unstemmed | Thermochromic Polymer Film Sensors for Detection of Incipient Thermal Damage in Carbon Fiber–Epoxy Composites |
| title_short | Thermochromic Polymer Film Sensors for Detection of Incipient Thermal Damage in Carbon Fiber–Epoxy Composites |
| title_sort | thermochromic polymer film sensors for detection of incipient thermal damage in carbon fiber epoxy composites |
| topic | thermochromism thermal damage detection epoxy-matrix composites fluorescence |
| url | http://www.mdpi.com/1424-8220/18/5/1362 |
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