The effects of glass-fiber sizings on the strength and energy absorption of the fiber/matrix interphase under high loading rates

Abstract

The interphases of various sized E-glass-®ber/epoxy-amine systems were tested at displacement rates in the range 230±2450 mm/s by a new experimental technique (dynamic micro-debonding technique). By this method, the rate-dependent interphase properties, apparent shear strength and absorbed energies due to debonding and frictional sliding, were quanti®ed. The systems include unsized, epoxy-amine compatible, and epoxy-amine incompatible glass ®bers. The high displacement rates that induce high-strain-rate interphase loading were obtained by using the rapid expansion capability of piezoelectric actuators (PZT). The results of dynamic micro-debonding experiments showed that the values of interphase strength and speci®c absorbed energies varied in a manner that is dependent on the sizing and exhibited signi®cant sensitivity to loading rates. The unsized ®bers exhibit greater frictional sliding energies that could provide better ballistic resistance, while the compatible sized ®bers show higher strength values that improve the structural integrity of the polymeric composites. In addition, signi®cantly higher amounts of energy are absorbed within the frictional sliding regime compared to debonding. By using the experimental data obtained, a case study was performed to reveal the importance of the interphase related micro damage modes on energy absorption (and therefore ballistic performance) of glass/ epoxy composite armor. #

Shear strength and fracture toughness of carbon fibre/epoxy interface: effect of surface treatment

“…This is in agreement with studies which claim that a weak interfacial bond dissipates more energy than a strong one and that micro-mechanisms such as fiber-matrix debonding or frictional fiber sliding are more important for energy absorption than macro-mechanisms such as delamination or matrix cracking under certain conditions [28,29]. Apparently, for future applications, the energy dissipation capacity of various forms of CFRCs, such as woven and braided textile, can be enhanced by designing a suitable interfacial bond between the fibre filaments and the polymeric matrix.…”

Preparation and Interfacial Properties of Glass Fiber/Polypropylene Microcomposites

“…In general, they are also nonconductive for electricity and nonmagnetic. Nowadays, FRP composites are widely used, mainly in defense, civil, aeronautic, and automotive industries, which are very rigorous about the performance of the materials used [5][6][7][8]. Thus, the means chosen to improve the performance of the glass fiber as a reinforcing material is a very important matter.…”

Investigating the effects of a polyester preforming binder on the mechanical and ballistic performance of E-glass fiber reinforced polyester composites

“…As a result of superior performance capabilities, PMCs are used widely in marine bodies, aircraft structures and armor for ballistic protection in military applications. Composite materials are also playing a key role in the development of polymer-composite/ceramic integral armor systems that contain multiple layers of glass fiber-reinforced PMCs [1][2][3][4][5][6]. For these applications, sized glass fibers are being employed with epoxy, vinyl ester and polyester resin systems.…”

“…For these applications, sized glass fibers are being employed with epoxy, vinyl ester and polyester resin systems. During dynamic loading of the composite structure, a variety of damage mechanisms including fiber/matrix interphase related micro-mechanisms such as fiber pull-out and macromechanism such as delamination at the interlaminar region may occur [5][6][7][8]. The mechanisms through which energy is absorbed during dynamic loading are critical to the ballistic or impact resistance of fiber-reinforced composites.…”