A comparative study of the compressive behaviour of 2099-T6 and 6061-T6 aluminum alloys under quasi-static and dynamic shock loading.

摘要

Aluminum 2099 is one of the recently developed aluminum alloys for high performancernaerospace applications. This alloy has been adequately characterized in tension underrnquasi–static loading. The current investigations focus on its behaviour in compressionrnunder both quasi-static and dynamic mechanical loading. The dynamic mechanicalrnloading was conducted by impacting the alloy with a blunt steel projectile at a momentumrnof 33 kg.m/s using an instrumented direct impact Hopkinson Bar. The deformationrnresponse of the 2099 aluminum alloy in the T6 tempered condition is discussed andrncompared with that of 6061-T6 aluminum alloy. Under the quasi–static loadingrncondition, plastic deformation is relatively homogeneous in both alloys, and is dominatedrnby strain hardening. Under the impact loading however, thermal softening plays arndominant role over strain hardening at the later stage of plastic deformation resulting inrnlow overall resistance to deformation. Similarly, deformation is also relativelyrnhomogeneous for 6061-T6 aluminum alloy under the impact momentum of 33 kg.m/s.rnIntense shear strain localisation leading to the development of adiabatic shear bandsrnoccur under the same impact loading condition for the 2099-T6 aluminum alloy. Thern2099–T6 aluminum alloy shows a better deformation resistance under quasi-staticrnloading while 6061-T6 aluminum alloy show superior mechanical behaviour under thernimpact loading.