A review of manufacturing processes, mechanical properties and precipitations for aluminum lithium alloys used in aeronautic applications

Abstract

Military applications and the aeronautic industry are increasingly interested in aluminum lithium alloys (Al-Li) because of the properties required due to the presence of Lithium, which provides a very considerable gain concerning the mechanical properties compared to conventional aluminum alloys. The research and development departments are interested in improving these alloys especially in additive manufacturing process, which leads today to focus on the 3rd generation of Al-Li in terms of part quality - low density compared to the 1st and the 2nd generation. The objectives of this paper is to present a review of Al-Li alloys applications, its carachetrization, the precipitations and their impact on mechanical properties and grain refinement. The various manufacturing processes, methods and tests used are then deeply investigated and presented. The last investigations that have been gotten by scientists over the previous few years on Al-Li for different processes are also reviewed in this research.

Keywords: Al–Li Alloys; Formability; Manufacturing processes; Mechanical properties.