A New 2nd Generation AlMgSc Alloy for Aerospace Applications

High pressure from the airlines on aircraft manufacturers with regard to fuel efficiency and maintenance costs of new aircrafts resulted in the past years in the development of new high performance aluminium alloys in order to compete against fiber reinforced composites or other advanced metals.

For short term drop-in solutions in derivative aircrafts or for advanced new aircraft types sheet alloys with superior properties and lower density compared to the standard fuselage alloy AA2024 are required to reduce the structural weight of the aircraft. In addition cost efficient and time saving manufacturing and assembly techniques have to be considered which allow for high production rates.

Thermally stable alloys such as AlMgSc alloys are suitable for conventional production routes as well as for advanced manufacturing techniques such as welding and relaxation forming. Due to their robustness a variety of processing parameters are possible without compromising on final properties. With their excellent damage tolerance properties, a very low density, and excellent corrosion resistance (no cladding required) these alloys offer additional benefits allowing for significant weight savings.

In this paper an advanced higher strength AlMgSc alloy will be presented. This alloy has been developed by Aleris targeting for a 10% higher strength than the standard solution (AlMgSc alloy AA5024) without compromising on other properties. It will be suitable for applications such as fuselage sheet or other sheet metal components where reduced weight and more cost efficient manufacturing routes are to be achieved.