Delamination shape effects in aramid‐epoxy‐aluminum (ARALL) laminates with fatigue cracks

Abstract

An aramid reinforced aluminum-epoxy-laminate, ARALL, which contains a fatigue crack and a delamination zone is analyzed. It is assumed that the interlaminar shear forces between the aluminum and aramid/epoxy layers are transmitted along the delamination boundary. The aramid/epoxy layer of the laminate is considered a series of linear springs. The tensile stress in the aramid/epoxy layer and the stress intensity factor in the aluminum layer are found for various experimentally observed delamination shapes. A residual strength criterion based on the maximum tensile stress in the aramid/epoxy layer is applied and the analytical results are correlated with the available experimental data.

Fatigue damage mechanisms in advanced hybrid titanium composite laminates

“…He verified the claims of Delft and Marrisen that fiber bridging was successful when promoted by controlled delaminations and that a significant "bridging zone" of 3-5 mm resulted. J. Macharet [21] of ALCOA Laboratories conducted an extensive research on the delamination shape in ARALL and showed that the larger the delamination area in the longitudinal direction, the less effective the fibers are in bridging and slowing crack growth. Davidson and Austin [20], using single edge notched specimens of ARALL, also showed a marked superiority of ARALL over monolithic aluminum due to fiber bridging at high AK levels.…”

Toughness and fracture mechanisms of glass fiber/aluminum hybrid laminates under tensile loading

“…: -;-82314005283, Fmc: +82 31406 5550 E-mail address:oschoi@hanyang.ac.kr tion due to the occurrence of local cavities in the FRP layer during the curing process, and to the formation of residual stress caused by their different thermal contractions between the Al and fiber layers. Although some kinds of FMLs are commercially available by the trade name of GLARE [8,9] or ARALL [10][11][12][13][14] their fracture characteristics and mechanisms associated with the Al kind, notch existence and fiber orientation are not sufficiently verified as tar as the authors know. Recently, the studies on FMLs have mainly focused on fatigue or impact characteristics of FMLs whose constituent fiber layer was unidirectional [8, 9,13,14].…”

“…Although some kinds of FMLs are commercially available by the trade name of GLARE [8,9] or ARALL [10][11][12][13][14] their fracture characteristics and mechanisms associated with the Al kind, notch existence and fiber orientation are not sufficiently verified as tar as the authors know. Recently, the studies on FMLs have mainly focused on fatigue or impact characteristics of FMLs whose constituent fiber layer was unidirectional [8, 9,13,14]. To apply FMLs in automobile components and infrastructures, further studies in relation to basic mechanical properties and fracture toughness of FIvILswith various lay-up angles should be carried out for their safety, integrity and reliability.…”