Quasi-Static Indentation Response of Galvanized Iron Toughened Glass Fiber/Epoxy Laminates

Abstract

This paper is aimed to study the quasi-static indentation response of fiber metal laminates (FMLs) that are made of various arrangement of galvanized iron (GI) alloy thin sheet, glass fibre and epoxy polymer. Unidirectional and woven types of glass fiber/epoxy pre-impregnated laminates and three different thickness of GI thin sheet, i.e. 0.5, 1.0 and 2.0 mm, were used to produce FML systems using combination of hand layup and hot press methods. The FML systems were coded as UGFRP, UGFML 1/2-2, UGFML 2/3-1, UGFML 4/5-0.5, WGFRP, WGFML 1/2-2, WGFML 2/3-1, WGFML 4/5-0.5 according to their types of glass fibers, thickness of GI and stacking sequence. Quasi-static indentation (QSI) tests were performed according to ASTM D6264 using hemispherical crosshead at 5 mm/min speed rate. It was found that both unidirectional and woven systems of FML 1/2-2 exhibited the highest energy absorption capacity, with enhancement of 28 times and 11 times more than UGFRP and WGFRP composite, respectively. At maximum compression, FML 2/3-1 displayed the highest ultimate load, while FML 1/2-2 displayed the highest displacement for both fiber systems. Damage area inspection revealed severe matrix crack, fiber fracture and delamination upon penetration and perforation.