Papers by Keyword: Interlaminar Number

Abstract: Currently, the most important objective in designing automobiles is to focus on environment-friendly and safety performance aspects. For the environment-friendly aspect, the issues relate to the shift towards lightweight automobile production, for improving fuel-efficiency and reducing exhaust fumes. However, in contrast, the issues of the safety performance such as crash safety, comfort level and muti-functional programs demand increase of automobile’s weight. Therefore, the design of automobile should be inclined towards the safety aspects, but at the same time, it also should consider reducing the structural weight of an automobile. In this study, for lightweight design of side member, CFRP side member was manufactured from CFRP unidirectional prepreg sheet. The stacking condition related to the energy absorption of composite materials, is being considered as an issue for the structural efficiency. Therefore, the axial collapse tests were performed with change of the stacking condition, such as fiber orientation angle and interlaminar number. The collapse modes and energy absorption characteristics were analyzed according to fiber orientation angle and interlaminar number.

Abstract: CFRP composite materials widely used as structural materials for airplanes, ships and aero space vehicles because of their high strength and stiffness. This study aims to investigate the effects of curvature and stacking sequence on the penetration characteristics of CFRP laminated shell. They are stacked to [02/902]S, [03/903]S and [02/903/0]S, [0/902/0]S, and their interlaminar numbers are two and four. We are manufactured to composite laminated shells with curvature radii of 100, 150, 200mm and ∞ (flat-plate), respectively. They were cure to the appropriate hardening temperature (130°C) at the vacuum bag of an autoclave. Composite laminated shells of dimensions 100㎜×140㎜ 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. In general, the kinetic energy after impact-kinetic energy before impact increased in all specimens. Absorbed energy increased as the curvature increased [03/903]S and [02/902]S which is small interlaminar number, was higher than four interlaminar specimen.