Damage tolerant behaviors of a biomimetic CFRP laminate

Abstract

The present work examines the damage tolerant behaviors of synthetic composites by using composite architectures observed in biological materials. The static, impact, and compression after impact (CAI) behaviors of biomimetic CFRP laminates with stacking sequences similar to those found in animal hard tissues are compared to those of a standard quasi-isotropic and a cross-ply laminates.The dependence of the extent of damage in the samples with a hole under tensile loading on the laminate lay-up was analyzed by a nite element analysis. The damage tolerance is then related to the actual damage extension from the hole perpendicularly to the applied load. It is shown that the damage tolerance of biomimetic laminate is more advantageous than the two other laminates. The implications of the ndings for the design of damage-tolerant laminates are further discussed.It is also shown from the results of compression after impact test that the sensitivity of biomimetic laminate to the presence of delamination damage is signi cantly lower than that of quasi-isotropicand cross-ply laminates.

Composites and Their Properties

“…Within the forewings of insects, both the laminated arrangement of the chitin fibers [Gullan & Cranstion, 1994;Leopoldj et al, 1992;Banerjee, 1988;Zelazny & Neville, 1972] and the mechanical characteristics of these equiangular laminating layers of the biomimetic composites [Tanimoto et al, 1998;Ben et al, 1998;Masuda et al, 1995] have been reported on previously. The authors have reported the presence of non-equiangular laminating structures in the forewing of A. dichotoma [Chen et al, 2001a].…”

The Lightweight Composite Structure and Mechanical Properties of the Beetle Forewing

“…Within the forewings of insects, both the laminated arrangement of the chitin fibers [Gullan & Cranstion, 1994;Leopoldj et al, 1992;Banerjee, 1988;Zelazny & Neville, 1972] and the mechanical characteristics of these equiangular laminating layers of the biomimetic composites [Tanimoto et al, 1998;Ben et al, 1998;Masuda et al, 1995] have been reported on previously. The authors have reported the presence of non-equiangular laminating structures in the forewing of A. dichotoma [Chen et al, 2001a].…”

Biomimetic Studies of the Beetle Forewing in China

“…However, the forewing of the beetle has long been mistakenly classified as nonliving matter [7], and perhaps due to this oversight, its inside microstructure has drawn little attention from biologists and bionic engineers. In the literature, studies have tended to focus on the following aspects of the beetle forewing: the composition of the chitin fiber (referred to as "fiber") and proteins [5,8,9,10], the stored internal air sacs [11], the chitin fiber layers themselves, which are of helicoidal structure [5,12], the orientation of chitin fibers [4,13,14], including the constant angle of fiber orientation [15] and dual spiral structures with small holes [16], and their influence on the mechanical properties of the biomimetic composite materials [13,17 ]. However, current knowledge on biomimetic composite materials is still limited.…”