The Behavior of Glass Fiber Composites under Low Velocity Impacts.

Autor: Păduraru I; 'Dunărea de Jos' University of Galati, Faculty of Engineering, Department of Mechanical Engineering, 800008 Galati, Romania., Ojoc GG; 'Dunărea de Jos' University of Galati, Faculty of Engineering, Department of Mechanical Engineering, 800008 Galati, Romania., Petrescu H; National University of Science and Technology 'Politehnica', Faculty of Industrial Engineering and Robotics, 060042 Bucharest, Romania., Graur I; 'Dunărea de Jos' University of Galati, Transfrontier Faculty, Department of Applied Sciences, 800008 Galati, Romania., Pîrvu C; National Institute for Aerospace Research 'Elie Carafoli', 061126 Bucharest, Romania., Deleanu L; 'Dunărea de Jos' University of Galati, Faculty of Engineering, Department of Mechanical Engineering, 800008 Galati, Romania.
Jazyk: angličtina
Zdroj: Polymers [Polymers (Basel)] 2023 Nov 27; Vol. 15 (23). Date of Electronic Publication: 2023 Nov 27.
DOI: 10.3390/polym15234549
Abstrakt: This paper presents experimental results on the behavior of a class of glass fiber composites under low velocity impacts, in order to analyze their usage in designing low velocity impact-resistant components in car and marine industries. Also, a finite element model at the meso level (considering yarn as a compact, homogenous and isotropic material) was run with the help of Ansys Explicit Dynamics in order to point out the stages of the failure and the equivalent stress distribution on the main yarns in different layers of the composite. The composites were manufactured at laboratory scale via the laying-up and pressing method, using a quadriaxial glass fiber fabric (0°/+45°/90°/-45°) supplied by Castro Composites (Pontevedra, Spain) and an epoxy resin. The resin was a two-component resin (Biresin ® CR82 and hardener CH80-2) supplied by Sika Group (Bludenz, Austria). The mass ratio for the fabric and panel was kept in the range of 0.70-0.77. The variables for this research were as follows: the number of layers of glass fiber fabric, the impact velocity (2-4 m/s, corresponding to an impact energy of 11-45 J, respectively) and the diameter of the hemispherical impactor (Φ10 mm and Φ20 mm) made of hardened steel. The tests were performed on an Instron CEAST 9340 test machine, and at least three tests with close results are presented. We investigated the influence of the test parameters on the maximum force (F max ) measured during impact, the time to F max and the duration of impact, t f , all considered when the force is falling to zero again. Scanning electron microscopy and photography were used for discussing the failure processes at the fiber (micro) and panel (macro) level. At a velocity impact of 2 m/s (corresponding to an impact energy of 11 J), even the thinner panels (with two layers of quadriaxial glass fiber fabric, 1.64 mm thickness and a surface density of 3.51 kg/m 2 ) had only partial penetration (damages on the panel face, without damage on panel back), but at a velocity impact of 4 m/s (corresponding to an impact energy of 45 J), only composite panels with six layers of quadriaxial fabric (5.25 mm thickness and a surface density of 9.89 kg/m 2 ) presented back faces with only micro-exfoliated spots of the matrix for tests with both impactors. These results encourage the continuation of research on actual components for car and naval industries subjected to low velocity impacts.
Databáze: MEDLINE
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje