Characterization of a fiber reinforced composite through use of ultrasonic scattering techniques

Fibers play a significant role in the strength and mechanical properties of fiber-reinforced composites (FRC). In micromechanics, it is important to know the elastic constants of both the fiber and matrix in an FRC. Considering the small diameter of commonly used fibers, it is not easy to experimentally measure their elastic constants except for their elastic modulus that can be obtained by a simple tensile test. The present study intends to measure both the elastic modulus and Poisson’s ratio of an isotropic fiber over a single shot through use of ultrasonic waves. The technique incorporates the formation of an inverse problem by combining experimental test results with results obtained from a mathematical model of the scattering process. The experimental results are obtained from ultrasonic wave scattering measurements from a single fiber. The inverse problem is then solved by using the genetic algorithm to find the elastic constants of the fiber. The measurement technique was found to be accurate and applicable to any fibers possessing circular cross-sections.

Keywords:

fiber-reinforced composite , characterization , elastic constants , ultrasonic , scattering