Nondestructive Damage Detection of a Magnetostrictive Composite Structure

Abstract

Abstract:The integrity of composite structures gradually degrades due to the onset of damage such as matrix cracking, fiber/matrix debonding, and delamination. Over the last two decades, great strides have been made in structural health monitoring (SHM) community using various sensing techniques such as acoustic emission, eddy current, strain gages, etc., to diagnose damage in aerospace, mechanical and civil infrastructures. Embedded sensing offers the prospects of providing for real-time, in-service monitoring of damage were weight savings is a major factor in Aerospace Industry. In this present work, magnetostrictive particles such as Terfenol-D were embedded in a composite structure, along with multiple SHM techniques, to capture the damage in an IM7-carbon fiber reinforced polymer composite system undergoing fatigue loading. As the internal stress state increases, the change in the magnetization flux intensity was captured using a non-contact magnetic field sensor. A damage diagnosis system was established along with an acoustic emissions technique to further validate the damage captured by the embedded system. The goal of this project is to identify the change in the mechanical and magnetic property within a composite material during the evolution of damage. Several characterization techniques were used to determine interfacial fiber-matrix interactions which will provide for a more comprehensive understanding of the composite interfaces.

The intersection of damage evaluation of fiber-reinforced composite materials with machine learning: A review

“…Nelon 161 investigated the combination of ML algorithms with magnetostrictive sensing 164–168 to detect the presence of delaminations in CFRP beams of varying ply count. A magnetostrictive material, such as Terfenol-D, couples magnetism with mechanics; under an applied magnetic field, one of these materials experiences deformation.…”

Construction and Numerical Realization of a Magnetization Model for a Magnetostrictive Actuator Based on a Free Energy Hysteresis Model

“…When magnetostriction is saturated, there is a certain hysteresis between the magnetostriction and the magnetic field strength, and its relationship is nonlinear. Because of the magnetostrictive effect and magnetostrictive inverse effect inside the giant magnetostrictive material, the two subsystems independent of each other between the magnetic system and the mechanical system are coupled [25,26]. At this time, if the giant magnetostrictive material is operated at a constant temperature, and only the strain in the longitudinal direction is considered, the magnetic field variables (magnetic field strength H, magnetic induction B) and mechanical field variables (stress σ, strain ε) are correlated with each other.…”