Fabrication and Experimental Analysis of Glass Fabric/Epoxy Honeycomb Sandwich Composite

The objective of the present work is to fabricate glass fabric/epoxy honeycomb core and to experimentally determine the shear strength and shear modulus of the core. Sandwich beams were fabricated by bonding glass fabric/epoxy face sheets (laminates) to glass fabric honeycomb core using epoxy resin. Three types of panels namely, unfilled honeycomb core, honeycomb core filled with polyurithene (PUR) foam and thermocol with an increase in thickness of the core in multiples of three were fabricated. The 3-point bending test in conformance with ASTM (C393-00) standard was conducted to experimentally obtain the flexural behavior and failure mode of the composite sandwich beams. It was observed that the load bearing capacity and core shear strength increased with increase in the thickness of the honey comb core filled with PUR foam. The bending strength is higher for the honey comb core filled with PUR foam when compared with the other cores. It is also observed that the bending strength for 6mm core is found to be high and decreases as the core thickness increases. It is found that injection of PUR foam improves the core properties of the panel. The study concludes by indicating that the glass fabric/epoxy honeycomb core can be used in sandwich construction for making low load bearing structures.