2. Experimental
The chemical composition of the 2196 Al-Li alloy is given in Table 1. The alloy is provided in the T8511
temper, which essentially includes the following: extruded, solution heat treated and stress relieved by stretching to
produce a nominal permanent set of 2.5%, and aged to T8511 temper. The 2196 Al-Li alloy is provided by
Canadian company Alcan in the T3511 temper as extrusions that can be used as stringers or stiffeners in aircraft
structures. Fig. 1 shows the curve of true stress and strain of 2196-T8511 obtained by tensile test. The tensile test
with the result that yield strength ıs= 527.15 MPa, tensile strength ıb = 592.82 MPa.
frames