Issue 51

G.S. Serovaev et alii, Frattura ed Integrità Strutturale, 51 (2020) 225-235; DOI: 10.3221/IGF-ESIS.51.18 227 Figure 1 : The scheme of the woven fabric (2  2 twill) [27]. Creation of a smart material, such as a polymer composite material with embedded optical fibers, requires ensuring the optical fiber integrity during the material manufacturing process, as well as strict adherence to all process parameters such as pressure, temperature and time, depending on the brand of material. The following steps were carried out according to the manufacturing technological process and the process of FOS embedding into PCM. At the first step, the cutting of the reinforcing material on the plotter Zund G3 L-2500 was carried out. After that, the layers of reinforcing material were laid out on special form-building equipment. The stack of layers for both materials (glass-fiber reinforced plastic and carbon fiber-reinforced plastic) consisted of 20 layers. Optical fibers, made from silica glass core and cladding with diameter of 0.124 mm and polyimide protective coating with thickness of 0.012 mm were embedded between 10 th and 11 th layers of composite material (Fig. 2). In order to align optical fiber in a straight line, small tension was applied. It should be noted that the most dangerous areas for optical fiber, embedded in composite material, are the input and output areas and to ensure its integrity, optical fiber was encapsulated into the Teflon tube in these zones. After performing all the operations mentioned above, the polymerization process was carried out in the Langzauner press. During the polymerization process, control of pressure and temperature was carried out by a control computer. After that, the technological package was removed. The recommended regime, according to the specifications of the materials, for the curing process is shown in Fig. 3 [28]. Figure 2 : The scheme of optical fiber placement between layers of the composite material. Figure 3 : The recommended regime for the curing process.