Original paper(Vol.45 No.7 pp.792)

Effect of lay-up sequence on relation between damage and absorbed energy in CFRP laminates subjected to falling weight impact

Nagai Isao; Tanaka Toshimitsu; Matsukawa Mami; Komaki Kazuo; Hojo Masaki

Abstract:The relation between damage and absorbed energy in four kinds of carbon/epoxy composite laminates was studied using an instrumented falling weight impact machine. Orthotropic and quasi-isotropic laminates, which were fabricated from unidirectional or plain woven prepreg, were used to investigate the effect of lay-up sequence. The thermal deply technique was applied to determine the extent of delamination and fiber breakage at various impact energy levels. In each kind of laminate, the absorbed impact energy showed a linear relation with the total delamination area and crack area of fiber breakage. No major difference was observed between orthotropic and quasi-isotropic laminates. Thus, the effect of lay-up sequence on the relation between damage and absorbed energy was negligible.

Key Words:composite material, reinforced plastic, instrumented impact test, impact damage, deply, delamination, fiber breakage, absorbed impact energy, effect of lay-up sequence