Prediction Of High Strain Rate Flow Behavior Of 7175 Aluminum Alloy Based On Arrhenius-Type Constitutive Equations

The flow behavior of 7175 aluminum alloy was modeled with Arrhenius-type constitutive equations using flow stress curves during a hot compression test. Compression tests were conducted at three different temperatures (250 degrees C, 350 degrees C, and 450 degrees C) and four different strain rates (0.005, 0.05, 0.5, and 5 s(-1)). A good consistency between measured and set values in the experimental parameters was shown at strain rates of 0.005, 0.05, and 0.5 while the measured data at 5 s(-1) showed the temperature rise of the specimen, which was attributable to deformation heat generated by the high strain rate, and a fluctuation in the measured strain rates. To minimize errors in the fundamental data and to overcome the limitations of compression tests at high strain rates, constitutive equations were derived using flow curves at 0.005, 0.05, and 0.5 s(-1) only. The results indicated that the flow stresses predicted according to the derived constitutive equations were in good agreement with the experimental results not only at strain rates of 0.005, 0.05, and 0.5 s(-1) but also at 5 s(-1). The prediction of the flow behavior at 5 s(-1) was correctly carried out by inputting the constant strain rate and temperature into the constitutive equation.