Interlaminar Fracture Toughness and Low-Velocity Impact Resistance of Woven Glass Epoxy Composite Laminates of EP3 Grade

N. Rajesh Mathivanan, J. Jerald

Department of Mechanical Engg., P. E. S. Institute of Technology, Bangalore - 85, India.
Dept. of Production Engg., National Institute of Technology, Tiruchirappalli - 15, India.

DOI: 10.4236/jmmce.2012.113024                

Abstract

This work presents the delamination resistance of woven glass fibre reinforced polymers (GFRP) and its influence on GFRP’s resistance to point impact. Two different types of laminates were fabricated by hand lay-up technique; (i) woven glass fibre epoxy matrix laminates and (ii) woven glass fibre epoxy matrix laminates with 3% graphite particulate fillers. End Notch Flexure (ENF) test was adopted for the measurement of delamination resistance. The two GFRPs laminates show similar mode II delamination resistance. At impact velocities between 2.215 and 4.429 m/sec, the GFRP developed a smaller damage size than the graphite-based GFRP laminates, indicating higher impact toughness. Difference of the impact resistance between the two GFRPs is mainly on the impact damage size developed. The total energy absorbed during the impact remains the same, which is independent of mode II delamination resistance of the GFRP. The history of relevant dynamic and energetic quantities, both to synthesize the dependency of the energy parameters and force threshold values on the impact velocity are discussed.

Keywords

Polymer matrix composite; Fibre; Laminates; Impact toughness.

Conflicts of Interest

The authors declare no conflicts of interest.

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