Evaluation of Tensile properties of FRP Composite Laminates under Varying Strain Rates and Temperatures

The present investigation deals with the characterization of tensile behavior of various Fiber Reinforced Polymer composites under Thermo-Mechanical loading. Five different types of Uni-Directional (UD) composites of Carbon, Glass, Carbon-Glass hybrid and Metal Laminates of Carbon & Glass were tested for tensile behavior. Tensile tests were performed at strain rates of 10^-3, 10^-2, & 10^-1 s^-1 at Room Temperature,250 ⁰C and 450 ⁰C. Stress-strain relations reveal the strain rate and temperature sensitive behavior of composites. Glass, Glass-Carbon, Glass-metal epoxy composites showed higher peak tensile stress under room temperature with varying strain rates as compared to neat carbon epoxy composites. Also, high strain rate tensile properties such as peak stress and peak strain of Glass-Carbon-Epoxy specimens were 26%, and 60% higher than that of the neat carbon epoxy composite. The failure mechanisms of both the composites were analyzed through scanning electron microscopy. The composites mainly failed due to matrix crack within elastic range under room temperature and failed with significant plastic deformation of matrix and fibers under test temperatures 250 ⁰C and 450 ⁰C. Finally, this study reveals that the continuous phase of metal layer embedded between Uni-Directional Glass and Carbon fiber, based composite system can be tailored to act as an energy-absorbing material system under both elastic and plastic stress strain regimes.