Comparative Mechanical Testing of Unidirectional Polymer Composite Materials

The paper presents the results of comparative tests of unidirectional basalt plastics. All tests are performed using three different methods, with their advantages and disadvantages being identified. A comparative analysis of the obtained experimental data is carried out including the assessment of strength, Young's modulus, and ultimate fracture strain. The most accurate values of strength characteristics (a=1571 MPa, E=42363 MPa) are obtained for samples manufactured by following the RF patent No. 2597811. These values are the closest to the theoretical ones calculated using the mixture rule and proper ratio of components. The implementation coefficients for characteristics of a reinforced filler and a binder of unidirectional samples produced in laboratory conditions are 0.7 for strength and 0.85 for Young’s modulus, calculated theoretically. Test results for the GOST 25.603-82 ring samples show almost twofold spread of obtained characteristics (strength varies from 500 to 1076 MPa, Young's modulus cannot be determined due to the method complexity). The GOST 33349-2015 samples have uneven thickness along their length and demonstrate unstable strength characteristics (a=1130 MPa, E=33052 MPa). They are lower than the characteristics of the RF patent No. 2597811 samples.