An AA6082-T6 disk 100 mm in diameter and 20 mm thick is open-die forged to 15...

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An AA6082-T6 disk 100 mm in diameter and 20 mm thick is open-die forged to 15 mm thickness in one operation at room temperature at an average strain rate of 100 s¹. In a second operation the disk is heated to 175°C and open-die forged to 10 mm thickness at an average strain rate of 100 s´¹. Assume the material follows the Johnson-Cooke material model with the form below and values of constants as A=428.5, B=327.7, C=0.00747, n=1.008, m-1.31, Tm-855 K, and To = 293.15. Calculate the work per unit volume in the second operation. (30 points) o = [A + Bɛ¹][1 + Clne* ] [1 - Tem] (1), where = €/o is the dimensionless strain rate for 80 = 1.0s¹ and A, B, C, n, and m are considered to be material constants. The relationship between the absolute temperature T in Kelvin, not Celsius, and the thermal softening term T* is expressed as T-To (2) where To is the room temperature and Tm the melting point, all in Kelvin, not Celsius. TM-TO T* = Assume the material follows the Johnson-Cooke material model with the form below and values of constants as A=428.5, B-327.7, C-0.00747, n=1.008, m=1.31, Tm-855 K, and TO = 293.15. Calculate the work per unit volume in the second operation. An AA6082-T6 disk 100 mm in diameter and 20 mm thick is open-die forged to 15 mm thickness in one operation at room temperature at an average strain rate of 100 s¹. In a second operation the disk is heated to 175°C and open-die forged to 10 mm thickness at an average strain rate of 100 s´¹. Assume the material follows the Johnson-Cooke material model with the form below and values of constants as A=428.5, B=327.7, C=0.00747, n=1.008, m-1.31, Tm-855 K, and To = 293.15. Calculate the work per unit volume in the second operation. (30 points) o = [A + Bɛ¹][1 + Clne* ] [1 - Tem] (1), where = €/o is the dimensionless strain rate for 80 = 1.0s¹ and A, B, C, n, and m are considered to be material constants. The relationship between the absolute temperature T in Kelvin, not Celsius, and the thermal softening term T* is expressed as T-To (2) where To is the room temperature and Tm the melting point, all in Kelvin, not Celsius. TM-TO T* = Assume the material follows the Johnson-Cooke material model with the form below and values of constants as A=428.5, B-327.7, C-0.00747, n=1.008, m=1.31, Tm-855 K, and TO = 293.15. Calculate the work per unit volume in the second operation.

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To calculate the work per unit volume during the second forging operation of the aluminum disk we can use the JohnsonCook material model to find the f... View the full answer