PSI - Issue 50

M.M. Kopyrin et al. / Procedia Structural Integrity 50 (2023) 137–146 M. M. Kopyrin et al. / Structural Integrity Procedia 00 (2019) 000 – 000

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It can be seen from the microphotographs that the basalt fabric has a denser interweaving between the fiber bundles compared to glass and carbon fabrics. This can be explained by the ratio of the number of twill weaves of bundles of basalt fibers - 5 to 3, while as in glass and carbon fabrics - 2 to 2. Fig. 3 shows diagrams comparing relative elongation and tensile strength of the original elastomer and elastomers reinforced with BF, GF, and CF layers.

a

b

Fig. 3. Physical and mechanical properties (a – Elongation; b - Tensile strength) of elastomers based on rubber SKD-V, SKD-V BF, SKD-V GF, SKD- V СF

When comparing the diagrams in Figure 3 a , it can be seen that the relative elongation after the introduction of the reinforcing layer into the elastomer matrix decreased by a factor of ~25-47 compared to the original rubber. For the elastomer with BF, the elongation value was 15.5%, for the elastomer with GF - 8.4%, for the elastomer with CF - 7.1%. Such a significant decrease in elasticity is explained by the inability of the reinforcing layers to large deformation changes. However, due to the introduction of a reinforcing layer into the rubber mixture, the values of the strength properties of composite elastomers have significantly increased (Fig. 3 b ). The strength of the samples increased from 1.7 to 2.8 times compared to the original rubber. The best result of strength properties among reinforced elastomers was shown by a sample with BF and was as high as ∼ 29 MPa. Reinforcement of SKD-V elastomer with high-strength fabrics made it possible to obtain materials with high strength properties and low rates of deformation changes. Fig. 4 shows micrographs of brittle fractures of SKD-V elastomers and composite elastomers with addition of a reinforcing layer.

Fig. 4. Microphotographs of specimen cleavages: a) SKD-V; b) SKD-V BF; c) SKD-V GF and d) SKD-V CF

The microphotographs of composite materials in Fig. 4 b-d show the contact points of the reinforcing fabric and the elastomeric matrix. The tightest contact is observed in the sample with BF due to its tight interlacing 5 to 3.