LOW-VELOCITY IMPACT RESPONSE OF GFRP/PU-Fe₂O₃ NANOPARTICLE-REINFORCED SANDWICH COMPOSITE PANELS BASED ON FORCE-DISPLACEMENT ANALYSIS AND NUMERICAL INTERPRETATION
Rathika M1., Paul Vizhian S2., Ashwini V.3
1,3Research Scholar, 2Professor, Department of Mechanical Engineering, University Visvesvaraya College of Engineering, Bangalore University, Bangalore, Karnataka, India
1Assistant Professor, Dr. Ambedkar Institute of Technology, Bangalore, India
Abstract: The low-velocity impact behavior of glass-fibre-reinforced polymer/polyurethane sandwich composite panels containing different concentrations of iron-oxide nanoparticles was investigated through experimental and numerical force–displacement analysis. Fe₂O₃ nanoparticles were incorporated into the polyurethane region at concentrations of 0, 1, 3 and 5 wt.% to study their influence on impact force, displacement, energy absorption, equivalent stress and equivalent strain. Experimental force–displacement curves were processed to determine peak impact force, loading energy, rebound energy and absorbed energy. Numerical force-displacement curves were generated from the experimental response to compare the behavior of the four material configurations. The experimental peak forces of the panels containing 0, 1, 3 and 5 wt.% Fe₂O₃ nanoparticles were 43.0, 47.1, 50.0 and 62.7 N, respectively. The panel containing 1 wt.% Fe₂O₃ nanoparticles recorded the highest absolute absorbed energy of 0.2561 J. The 5 wt.% panel recorded the lowest rebound energy of 0.0073 J and the highest absorbed-energy percentage of 97.09%. The numerical force-displacement response showed an increase in peak force and a decrease in displacement at peak force with increasing Fe₂O₃ nanoparticle content. The maximum equivalent stress increased from 38.5 MPa for the unfilled panel to 59.2 MPa for the 5 wt.% panel, while the equivalent strain decreased from 1.95% to 1.41%. The results show that Fe₂O₃ nanoparticle reinforcement increased panel stiffness, improved load transfer and reduced impact deformation. The 1 wt.% composition provided the highest absolute energy absorption, whereas the 5 wt.% composition provided the highest peak-force resistance and absorbed-energy percentage.
Keywords: Fe₂O₃ Nanoparticles; Iron-oxide Nanoparticles; GFRP; Polyurethane; Sandwich Composite; Low-velocity Impact; Force-displacement Response; Absorbed Energy; Equivalent Stress.
VOLUME 10 ISSUE 08 2026: 1 – 21