Smart fibers and products for aerospace applications

<p indent="0mm">Smart fibers have functions such as sensing, communication, signal processing, etc., and can respond to external stimuli. When integrated into traditional high-performance fiber fabrics, they attract widespread attention in the aerospace field. Through real-time monitoring and active control, they greatly enhance the safety and reliability of aircraft. This review mainly introduces four main smart fibers according to their sensing mechanisms: Piezoelectric fibers, piezoresistive fibers, shape memory fibers, optical fiber materials. Then manufacturing methods of these smart fibers and products are summarized from 1D fiber to 2D and 3D textile structures. We review the latest research progress of smart fibers and fabrics in the aerospace field, including their applications in structural health monitoring, energy harvesting, vibration and noise control, etc. In terms of structural health monitoring, smart fibers are directly integrated into composite materials, such as those used for aircraft skins, eliminating the problem of multiple sensors and large volume occupation in traditional structural health monitoring. They can identify multiple failure modes, achieve real-time monitoring of many parameters such as stress, strain, and temperature simultaneously, and collect data to timely warn of potential damage, which is able to reduce maintenance costs. For energy harvesting, fiber materials with piezoelectric, thermoelectric, and triboelectric effects can be embedded in locations such as wings and fuselages, effectively converting vibration and thermal energy generated during flight into electrical energy to provide power for sensors and other on-board electronics, reducing the vehicle’s dependence on large-mass energy storage devices and thus improving flexibility. Moreover, these fibrous materials can usually be used in conjunction with flexible and lightweight energy storage devices to maximize energy savings and efficiency. In terms of vibration and noise control, currently, smart materials based on the inverse piezoelectric effect of piezoelectric fibers are designed to combine active and passive control to suppress the unwanted vibration of structures, thereby enhancing the stability and comfort. This review also points out that smart fibers in the aerospace field will develop towards high integration and intelligence, involving: (1) Development of new smart fiber materials, such as the introduction of functionalized coatings to enhance the functional integration of fiber materials, and the development of self-repairing fiber materials to refine the service life of smart fiber electronic devices. (2) Optimization of the manufacturing processes to achieve mass production of fiber materials in a simple and efficient way. (3) Improvement of the reliability and durability of smart fibers in practical applications. Structural modification and other methods should be taken to ensure reliable performance of the fiber material in use. (4) Development of multi-functional integrated smart fibers. Through continuous research and innovation, smart fibers and textiles can achieve more extensive and in-depth applications in the aerospace field, thereby providing strong support for improving the performance and safety of aerospace vehicles.