Self-Sensing Hybrid Fibre-Reinforced Polymer for Structural Health Monitoring (SHM)

Abstract

Hybrid composite material has been widely used in many engineering applications (e.g., for automobiles)and has several advantages over conventional fibre-reinforced composite materials, such as high strength-to-weight ratio and low cost. However, combining two kinds of reinforcement fibre within a common matrix may lead to different failure modes, such as delamination between the layers and fragmentation when the structure is subjected to high loads. To avoid this problem, real-time damage detection should be integrated into the hybrid composite structures for structural integrity. This paper outlines the working mechanisms and the initial fabrication of an integrated capacitive sensor into the intra-ply hybrid composite. The tensile test was conducted to perform the basic characterization of the proposed sensor and provide self-sensing functionality (smart structure). The results illustrate that damage between layers can be detected by in-situ monitoring. It is shown that the initial damage was detected at the turning point where the relative change in capacitance begins to decrease and when the axial tensile force increases. In addition, the developed smart material has shown a linear sensitivity toward crosshead displacement up to the turning point, and applying the monitoring is useful in self-sensing for hybrid composites.

Develop a Smart Material Based on Carbon-Aramid Hybrid Composite for Health Monitoring Structure

“…The onset of deterioration or failure occurred at the turning point where the capacitive value began to decrease. It has been shown that the embedded sensor into the Kevlar-carbon composite had a linear response over a broad range of axial stress (up to 170 MPa) compared to it embedded into a glass-carbon hybrid composite which is up to 100 MPa [3]. The observed improvement may be attributed to a significant difference of the Young's modulus between glass and carbon fibers which was minimized by hybridization of Kevlar fibers with carbon fibers, in turn leading to delaying the onset of failure at the turning point.…”

Structural Health Monitoring of Fiber Reinforced Composites Using Integrated a Linear Capacitance Based Sensor

“…Their findings indicated that damage occurred at an early stage of axial stress. In a study by Alblalaihid et al [ 29 , 30 ], a smart intra-ply hybrid composite material (comprising glass fiber and carbon fiber) based on capacitance was developed. It was observed that failure occurred at a low level of axial stress due to the combination of low-elongation and high-elongation fibers within a common matrix.…”