Integration of optical fibers and piezoelectric ceramics in composite materials

1996 ◽  
Author(s):  
S. Bourasseau ◽  
Marc Dupont ◽  
M. Pernice ◽  
Alain Thiriot ◽  
P. Blanquet ◽  
...  
Keyword(s):  
Composite Materials ◽  
Optical Fibers ◽  
Piezoelectric Ceramics

scholarly journals Damage detection in laminar thermoplastic composite materials by means of embedded optical fibers

2006 ◽  
Vol 60 (7-8) ◽  
pp. 176-179
Author(s):  
Aleksandar Kojovic ◽  
Irena Zivkovic ◽  
Ljiljana Brajovic ◽  
Dragan Mitrakovic ◽  
Radoslav Aleksic
Keyword(s):  
Composite Materials ◽  
Optical Fiber ◽  
Real Time ◽  
Optical Fibers ◽  
Impact Damage ◽  
Experimental Testing ◽  
Low Energy ◽  
Thermoplastic Composite ◽  
Woven Fabric ◽  
The Impact

This paper investigates the possibility of applying optical fibers as sensors for investigating low energy impact damage in laminar thermoplastic composite materials, in real time. Impact toughness testing by a Charpy impact pendulum with different loads was conducted in order to determine the method for comparative measurement of the resulting damage in the material. For that purpose intensity-based optical fibers were built in to specimens of composite materials with Kevlar 129 (the DuPont registered trade-mark for poly(p-phenylene terephthalamide)) woven fabric as reinforcement and thermoplastic PVB (poly(vinyl butyral)) as the matrix. In some specimens part of the layers of Kevlar was replaced with metal mesh (50% or 33% of the layers). Experimental testing was conducted in order to observe and analyze the response of the material under multiple low-energy impacts. Light from the light-emitting diode (LED) was launched to the embedded optical fiber and was propagated to the phototransistor-based photo detector. During each impact, the signal level, which is proportional to the light intensity in the optical fiber, drops and then slowly recovers. The obtained signals were analyzed to determine the appropriate method for real time damage monitoring. The major part of the damage occurs during impact. The damage reflects as a local, temporary release of strain in the optical fiber and an increase of the signal level. The obtained results show that intensity-based optical fibers could be used for measuring the damage in laminar thermoplastic composite materials. The acquired optical fiber signals depend on the type of material, but the same set of rules (relatively different, depending on the type of material) could be specified. Using real time measurement of the signal during impact and appropriate analysis enables quantitative evaluation of the impact damage in the material. Existing methods in most cases use just the intensity of the signal before and after the impact, as the measure of damage. This method could be used to monitor the damage in real time, giving warnings before fatal damage occurs.

Laminar Composite Materials Damage Monitoring by Embedded Optical Fibers

2008 ◽  
pp. 1035-1036 ◽  
Author(s):  
Aleksandar Kojovi ◽  
Zivkovi Irena ◽  
Ljiljana Brajovi ◽  
Dragan Mitrakovi ◽  
Radoslav Aleksi
Keyword(s):  
Composite Materials ◽  
Optical Fibers ◽  
Laminar Composite ◽  
Damage Monitoring

scholarly journals Polymer Fibers Covered by Soft Multilayered Films for Sensing Applications in Composite Materials

Sensors ◽  
2019 ◽  
Vol 19 (18) ◽  
pp. 4052 ◽  
Author(s):  
Dorian Nikoniuk ◽  
Karolina Bednarska ◽  
Maksymilian Sienkiewicz ◽  
Grzegorz Krzesiński ◽  
Mateusz Olszyna ◽  
...  
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Optical Fibers ◽  
Temperature Sensitivity ◽  
Polymer Coating ◽  
Layer By Layer ◽  
Sensor Applications ◽  
Sensing Applications ◽  
Polymer Optical Fibers ◽  
Soft Polymer

This paper presents the possibility of applying a soft polymer coating by means of a layer-by-layer (LbL) technique to highly birefringent polymer optical fibers designed for laminating in composite materials. In contrast to optical fibers made of pure silica glass, polymer optical fibers are manufactured without a soft polymer coating. In typical sensor applications, the absence of a buffer coating is an advantage. However, highly birefringent polymer optical fibers laminated in a composite material are much more sensitive to temperature changes than polymer optical fibers in a free space as a result of the thermal expansion of the composite material. To prevent this, we have covered highly birefringent polymer optical fibers with a soft polymer coating of different thickness and measured the temperature sensitivity of each solution. The results obtained show that the undesired temperature sensitivity of the laminated optical fiber decreases as the thickness of the coating layer increases.

Highly birefringent polymer microstructured optical fibers embedded in composite materials

2013 ◽  
Author(s):  
P. Lesiak ◽  
M. Szeląg ◽  
M. Kuczkowski ◽  
A. W. Domański ◽  
T. R. Woliński
Keyword(s):  
Composite Materials ◽  
Optical Fibers ◽  
Microstructured Optical Fibers

Strain measurement and cure monitoring in thin plates of composite materials by using twisted optical fibers

1996 ◽  
Author(s):  
Huiwen Wang ◽  
Jan Wu ◽  
Naiji Li ◽  
Hongjun Cao ◽  
Di Dai ◽  
...  
Keyword(s):  
Composite Materials ◽  
Optical Fibers ◽  
Strain Measurement ◽  
Thin Plates ◽  
Cure Monitoring

scholarly journals The usage of optical fibers for damage detection in ballistic protection composite laminates

2006 ◽  
Vol 60 (1-2) ◽  
pp. 39-44
Author(s):  
Irena Zivkovic ◽  
Aleksandar Kojovic ◽  
Milos Tomic ◽  
Ljiljana Brajovic ◽  
Radoslav Aleksic
Keyword(s):  
Composite Material ◽  
Composite Materials ◽  
Optical Fibers ◽  
Signal Intensity ◽  
Light Signal ◽  
Thermoplastic Composite ◽  
Damage Resistance ◽  
Applied Loading ◽  
Reinforced Composite ◽  
Photo Detectors

This paper describes the procedure of embedding fiber optic sensors in laminar thermoplastic composite material, as well as damage investigation after ballistic loading. Thermoplastic-reinforced composite materials were made for increased material damage resistance during ballistic loading. Damage inside the composite material was detected by observing the intensity drop of the light signal transmitted through the optical fibers. Experimental testing was carried out in order to observe and analyze the response of the material under various load conditions. Different types of Kevlar reinforced composite materials (thermoplastic, thermo reactive and thermoplastic with ceramic plate as the impact face) were made. Material damage resistance during ballistic loading was investigated and compared. Specimens were tested under multiple load conditions. The opto-electronic part of the measurement system consists of two light-emitting diodes as light sources for the optical fibers, and two photo detectors for the light intensity measurement. The output signal was acquired from photo detectors by means of a data acquisition board and personal computer. The measurements showed an intensity drop of the transmitted light signal as a result of the applied loading on composite structure for all the optical fibers. All the diagrams show similar behavior of the light signal intensity. In fact, all of them may be divided into three zones: the zone of penetration of the first composite layer, the bullet traveling zone through the composite material till its final stop, and the material relaxation zone. The attenuation of the light signal intensity during impact is caused by the influence of the applied dynamic stress on the embedded optical fibers. The applied stress caused micro bending of the optical fiber, changes in the shape of the cross-section and the unequal changes of the indices of refraction of the core and cladding due to the stress-optic effect. The main goal of the experiment was to develop a system for thermoplastic composite structure health monitoring during real life exploitation. The results of the experiments confirmed that optical fibers could be applied as intensity sensors in the real-time monitoring of structural changes in thermoplastic laminar composite materials under ballistic loading. The light signal intensity drops in an optical fiber in response to the applied loading on the composite material.

Sign in / Sign up

Export Citation Format

Share Document