A cylindrical part is warm upset compressed by forging in an open die. Before forging, the diameter axially is 20mm and the height is 60mm. The coefficient of friction at the die-work interface is 0.20. The flow curve of the work material at forging temperature is defined by a strength coefficient of K is 530MPa, and a strain-hardening exponent of n is 0.23. Assume the volume of the part remained unchanged during the whole process and no barreling effects.

a. The maximum strain of the part is 0.485. What is the maximum area of contact between the die and the part?
b. What is the maximum force required to forge this part to its maximum area?