Investigation of a new fibre metal laminate (FML) family on the base of Al‐Li‐Alloy with lower density

Abstract

AbstractThe hybrid Fiber Metal Laminate (FML) GLARE (Glass Laminate Aluminium Reinforced Epoxy) is applied effectively by Airbus instead of monolithic aluminum alloys for lowering of weight and increase of the damage tolerance capability on the largest civil aircraft A‐380. Standard GLARE contains thin aluminum sheets of 2024T3 (duralumin type) alloy, which is used usually as a skin alloy because it provides high fatigue and damage tolerance properties as well as a high ductility. One of advanced ways of further FML development is an application of thin sheets from processable Al‐Li Russian high‐modulus (E = 80 GPa) 1441 alloy with lower density (d = 2.60 g/cm3). This results in further weight saving but also to an increase of stiffness of the FML‐structure by 5–7%. Investigations and tests of coupons, components, joints and panels from 1441‐FML are carried out by Airbus, Russian and Dutch partners. Various resins and glass fiber types were also used. It was shown that generally 1441‐FML properties can be compared to Standard GLARE, i. e. an 1‐to‐1 substitution of the 2024 sheets into 1441 sheets is an option in order to obtain the full weight saving advantage due to the density effect.