Hot Workability Of 2A11 And 2A12 Aluminum Alloys

Al-Cu-Mg alloys,heat-treatable aluminum alloys,are widely used for the transportation and aircraft industry.In this paper,the hot compression tests of 2A11and 2A12 aluminum alloys were performed on Gleeble-3500 system at strain rate of0.01-10 s^-1and deformation temperature of 300-450?.The results show as follows:(1)The true stress-true strain curves exhibit a peak stress at a critical strain,then the flow stresses decrease monotonically until high strains,showing a dynamic flow softening.The flow stress increase with increasing strain rate and decreasing deformation temperature,while the peak stresses for 2A12 alloy are higher than those for 2A11 alloy under the similar compression conditions.(2)The flow stresses can be represented by the Zener-Hollomon parameter Z in the hyperbolic-sine equation.The hot deformation activation energy for 2A12 alloy is lower than that for 2A11 alloy under the similar deformation conditions.(3)The processing maps of hot working for both alloys were obtained by using dynamic materials model(DMM).The optimum parameters for 2A12 alloy are deformation temperature of 400-450?and strain rate of 0.01-0.1 s^-1while for 2A11alloy is 300-450?and 0.01-10 s^-1.