Characterization of Energy Absorption Capability of Composite Materials Subjected to Impact Loading

摘要

Delamination is a critical damage mode in laminated composite materials subjected to transverse impacts. Once delamination takes place, a composite laminate becomes disintegrated and can be perforated easily. Both fiber geometry design and reinforcing technique are commonly used in improving composite materials with higher delamination resistance, and hence higher impact resistance. This study was focused on composite lamination design. The study began with a small-angle composite laminate [O_4/I5_4/O_4]. A single-axis composite laminate [(0/15)_3]_s was found to be an optimal variation due to its high lamina constraint and high delamination resistance. In order to meet various design requirements, a double-axis laminate [(0/15)/(90/-75)]_3, a triple-axis laminate [(0/15)/(60/75)/(-60/-45)]_2 and a sextuple-axis laminate [(0/15)/(30/45)/(60/75)/(90/-75)/(-60/-45)/(-30/-15)] were also investigated and found to have similar impact resistance as the single-axis one. The introduction of these multiple-axis composite laminates provided a way to achieve the structural requirements for both high stiffness and high impact resistance.