Method for integrating composite material structure with optical fiber

Abstract

The invention discloses a method for integrating a composite material structure with an optical fiber. The method comprises the following steps: 1) preparing a composite material structure formed by prepreg; (2) the composite material structure is pretreated; 3) selecting an optical fiber with a high-temperature-resistant coating layer as a sensor, temporarily fixing the optical fiber by using glue, and laying the optical fiber on the surface of the composite material structure according to the layout design; 4) covering the temporarily fixed optical fiber with the adhesive film; (5) the adhesive film is heated through a heating device, so that the adhesive film has viscidity and can be temporarily fixed to the composite material structure; 6) covering a layer of prepreg with the same structure as the composite material on the adhesive film; and 7) performing secondary high-temperature and high-pressure curing on the composite material structure on which the optical fiber is laid according to a curing process of the used prepreg, thereby obtaining the prepreg. The subsequently integrated optical fiber does not affect the structural strength performance, the direction of the optical fiber and the direction of the fiber in the prepreg can be adjusted at will, and the strain transmission efficiency is improved; meanwhile, the advantages of two schemes of surface pasting and internal implantation are realized.

Description

technical field [0001] The invention relates to the technical field of composite material structures, in particular to a method for integrating optical fibers with composite material structures. Background technique [0002] Composite materials have high specific modulus and specific strength, and are more and more widely used in aerospace structures, bringing significant weight reduction benefits to aircraft. However, due to manufacturing defects or impact, the composite structure is prone to damage such as delamination, degumming, and crushing, which reduces flight safety and increases maintenance costs. Researchers integrated sensor networks in composite structures to conduct online health monitoring to detect damage in time to improve flight safety and reduce maintenance time and costs. Optical fibers have broad application prospects in the health monitoring of composite structures by virtue of their slenderness, light weight, high temperature and high pressure resistan...

AI Technical Summary

Problems solved by technology

(1) The former is to use glue such as epoxy glue to paste the optical fiber on the surface of the structure after the composite material structure is fabricated. This method has the advantages of flexible layout, convenient replacement, and no impact on the structural strength performance. It is easy to be debonded or damaged in the environment, and the optical fiber and the structure are not tightly combined, and the strain transmission is poor

(2) The latter is to lay the optical fiber between the prepreg layers during the manufacturing process of the composite structure, or weave the optical fiber into the fiber reinforcement and then perfuse the resin, and finally cure and shape. The advantage of this method is that the optical fiber is not affected by the environment and damage, and the optical fiber is tightly combined with the structure, and the strain transmission is good, but the disadvantage is that the diameter of the optical fiber is larger than the reinforcing fiber, which is equivalent to impurities, which will affect the strength performance of the structure, especially when the fiber laying direction is perpendicular to the direction of the reinforcing fiber, the impact is the greatest, so The direction of fiber laying is limited

Both methods have certain defects, which greatly limit the engineering application of optical fiber sensing in health monitoring of composite structures

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