Specific Energy Absorption Capacity of Glass-polyester Composite Tubes under Static Compressive Loading

INTRODUCTION Composite materials are often used to reduce the weight of structures. In the automotive industry weight reduction is important because fuel consumption is directly related to vehicular weight. There is an increased concern for occupant safety during roadway accidents. Metals are currently used in car frames and integrated frame-body structures, and these and other metallic components are designed to passively absorb energy during accidents. However, automotive manufacturers are moving toward nontraditional materials 1 and new structural material under consideration should be capable of participating in the energy absorption process associated with accidents. An important parameter when studying energy absorption, and one often used in the automotive industry, is the energy absorbed per unit mass of crushed material. This is often called the specific energy absorption (SEA) 2 . The SEA provides a measure of energy absorption efficiency of a structural component but, of course, says nothing about the efficiency of the structure in regards to other areas, such as resisting buckling, damping vibrations, or its ease of manufacture. It is one of several parameters that must be considered in automotive design. The subject of the paper 3 was investigation of the effect of interlaminar fracture toughness on the specific energy absorption of stitched glass/polyester composite cylindrical shells under axial compression. The laminated composite cylindrical shells, used as energy absorbers, absorb large amount of impact energy during collision. Since delamination in the thin wall of axially collapsed shell is one of the major energy absorbing modes, contribution to SEA of tubes is significant during collision. The energy absorbing capability of fiber reinforcement polymer (FRP) composite cylindrical tubes used as energy absorbers, by destroying itself progressively, depends on the way in which tube material is crushed i.e., trend of petalling [4]. This paper investigates the influence of fibre orientation and stacking sequence on the petal formation and specific energy absorption (SEA) of glass/polyester composite cylindrical shells under axial compression. Processing conditions effect on specific energy absorption capacity of composite tubes was investigated in 5 . Tubes of circular and square cross sections were fabricated using orthophthalic polyester resin and plain weave E-glass fabric with fibers oriented at 0° / 90°, with respect to the tube axis. Test specimens consisting of tube segments were prepared and tested under static compression load. Very important factor in the study of energy absorption for energy management capabilities is the shape of