CFRP 부재의 적층구성에 따른 관통저항 특성

Abstract

In this paper CFRP composite materials widely used as structural materials for airplanes, ships and aero space vehicles because of their high strength and stiffness. However, this material has a drawback of weakness against a transverse impact loading acting toward the direction of its stacked thickness, which requires different design parameters other than those used for general metal products in actual application. Therefore, to utilize a laminated composite material for structural component, impact behaviors, damage analysis and penetration characteristics against transverse impact loading must be studied essentially in the first place, and impact and penetration experiments for laminated composite material shell curved to actual body shape of the structural component must be conducted in advance to any others. In connection with this point of view, this study utilized specimen of laminated composite material shell having certain radius of curvature considering actual structural component made of laminated CFRP composite material. Autoclave forming of CFRP process is the most commonly used method of applying heat and pressure simultaneously. This process is suitable for the structural aerospace and military applications which needs a high mechanical properties assisted by removal of trapped air or other volatiles. This study aims to investigate the effects of stacking sequence and distance on the penetration characteristics of CFRP laminated plates. They are stacked to [03/903]s, [02/903/0]s, [0/902/02/90]s, and their interlaminar numbers are two and six. They are distance to 0mm ?` 30mm, and their real distance are 100mm ?`300mm. Composite laminated plates of dimensions 180mm⨯180mm were prepared. The velocity of the steel ball that transversely impacts a specimen was measured both before and after impact by determining the time for the ball to pass two ballistic-screen sensors located at a known distance apart.