Enhanced-performance active fiber composites

Active fiber composites are among the many other components used in intelligent and smart composite structures which undergo mechanical deformation upon the application of external loads or electric fields. This work presents an analytical approach for derivations of exact solutions for the effective axial mechanical properties of active fiber composites with circular cross-sections, and while the properties of the constituent materials are considered to be generally orthotropic. First, exact analytical solutions of the effective longitudinal Young’s modulus and Poisson’s ratio are obtained for a three-phase composite cylindrical model composed of orthotropic materials. Next, Finite element analysis, as an alternative approach, is performed to numerically determine the effective axial properties of an identical three-phase composite cylinder. Finally, effective material properties obtained from analytical and finite element methods are compared to verify the derived analytical solutions. Excellent agreements are achieved between the results obtained from both techniques validating the exact analytical solutions.

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Self-Detection of Delamination in Active Fiber Composites

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.56.447 ◽

2008 ◽

Vol 56 ◽

pp. 447-452

Author(s):

Dwo Wen Wang ◽

Wen Chih Tsai ◽

Ching Chung Yin

Keyword(s):

Fiber Composites ◽

Acoustic Sensors ◽

Sinusoidal Voltage ◽

Electric Impedance ◽

Frequency Range ◽

Bonding Condition ◽

Active Fiber ◽

Interdigital Electrodes ◽

Novel Method ◽

Active Fiber Composites

This paper presents a novel method to monitor the bonding condition of active fiber composites (AFCs). AFCs can be used as integrated acoustic sensors/actuators to compose functional structures because of their excellent properties. Debonds between AFC patch and host structure should be avoided and surveyed through its service life. A partially debonded patch bears an axial extensional vibration which is excited by a sinusoidal voltage and detected by the interdigital electrodes symmetrically aligned on opposite surfaces of the patch. The electric impedance and mechanical displacement of the AFC patch adhered on an aluminum plate were investigated in a broad frequency range. The modal characteristics depend on the size of debond and stiffness of adhesive in front of the edge of delamination. The debonding ratio of the AFC patch is in inverse proportion to the resonant frequency of the fundamental mode. Feasibility of self-detecting the progressive delamination between AFC patch and host plate is demonstrated through computational and experimental results.

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Characterization and modeling time dependent behavior in PZT fibers and active fiber composites

10.1117/12.2084811 ◽

2015 ◽

Author(s):

Mohamed A. Dridi ◽

Hassene B. Atitallah ◽

Zoubeida Ounaies ◽

Anastasia Muliana

Keyword(s):

Fiber Composites ◽

Time Dependent ◽

Active Fiber ◽

Dependent Behavior ◽

Active Fiber Composites

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