Issue 53

E. M. Strungar et alii, Frattura ed Integrità Strutturale, 53 (2020) 406-416; DOI: 10.3221/IGF-ESIS.53.31 412 For experimental study of deformation processes and accumulation of damages in carbon fiber composite samples with internal defects under complex stressed conditions the authors implemented mechanical tests at proportional extension/compression with torsion at k=0.028 (k=u/ φ ). To assess the internal defect development the tests were conducted with three unloadings and repeated loadings. In the event of internal defect development in the process of loading the change of deformation fields pattern is recorded (Fig. 9) [13,14]. Figure 8: The diagrams of sample deformation using the instruments “virtual extensometer T” and “rectangular area R” to determine shear deformations. Figure 9: Non-homogeneous longitudinal strain fields on the sample surface with the defect size 10 х 10 mm. Figure 10: Longitudinal strain fields evolution and the corresponding thermograms depending on the number of performed loading cycles.