Tension behavior of unidirectional glass/epoxy composites under different strain rates

• Published in: Composite structures Vol. 88; no. 4; pp. 595 - 601
• Main Authors: Shokrieh, Mahmood M., Omidi, Majid Jamal
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.05.2009; Elsevier
• Subjects: Applied sciences; Composites; Dynamic loading; Exact sciences and technology; Forms of application and semi-finished materials; Fracture mechanics (crack, fatigue, damage...); Fundamental areas of phenomenology (including applications); Physics; Polymer industry, paints, wood; Polymeric composites; Solid mechanics; Strain rate effects; Stress–strain curve; Structural and continuum mechanics; Technology of polymers; Tensile properties; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...); Polymeric composites; Strain rate effects; Tensile properties; Dynamic loading; Stress–strain curve; Hydraulic control; Fiber reinforced material; Test bar; Work holder; Composite material; Dynamic test; Glassy polymer; Focusing; Size effect; Material testing; Uniaxial load; Static test; Strain rate; Stress strain relation; Unidirectional fiber material; Rupture; Quasi static theory; Tensile property; Experimental study; Clamping; Tension test; Glass fiber; Dynamic load; Stress-strain curve
• ISSN: 0263-8223; 1879-1085
• DOI: 10.1016/j.compstruct.2008.06.012

By considering wide applications of composite materials, having a proper knowledge of them under dynamic loading is necessary. In order to study the effects of strain rates on the behavior of the materials, special testing machines are needed. Most of the research in this field is focused on applying real loading and gripping boundary conditions on the testing specimens. In this study, behavior of unidirectional glass fiber reinforced polymeric composites under uni-axial loading is determined at quasi-static and intermediate strain rates of 0.001–100 s −1. The tests were performed using a servo-hydraulic testing apparatus equipped with a strain rate increase mechanism. For performing the tests, a jig and a fixture are designed and manufactured. The performance of the test jig was evaluated and found to be adequate for testing of composites. Dynamic tests results are compared with the results of static tensile tests carried out on specimens with identical geometry. Experimental results show a significant increase of the tensile strength by increasing the strain rate. The tensile modulus and strain to failure are also observed to increase slightly by increasing the strain rate.