Buckling strength of FML profiles of ‘classic’ versus thin-ply design

Abstract

The past few decades have seen the introduction of fiber metal laminates (FMLs), especially GLARE, into primary structure applications such as the fuselage of the largest civil transport aircraft in current production: the Airbus A380. GLARE material properties, as well as FMLs in general, exhibit partly metallic and partly composite behaviour. The hybrid nature of FML has several advantages when compared with monolithic aluminium application to fuselage skins, i.e. lower density and crack arresting capability of the fiber layers in presence of a fatigue cracks, which are a major concern in the design of monolithic aluminium . The possibility to tailor the material to meet specific structural or mechanical requirements, by appropriate orientation of the fibers layers, is especially important. These features allow to some extent the concerns about `flying with undetectable fatigue damage´, which influences inspection intervals and the economics of airframe maintenance