A cylindrical workpiece is subjected to a cold upset forging operation. The starting piece is 75 mm in height and 50 mm
Posted: Tue Jun 07, 2022 3:00 pm
A cylindrical workpiece is subjected to a cold upset forging operation. The starting piece is 75 mm in height and 50 mm in diameter. It is reduced in the operation to a height of 36 mm. The work material has a flow curve defined by K = 350 MPa and n=0.17. Assume a coefficient of friction of 0.1. Determine the force as the process begins, at intermediate heights of 62 mm, 49 mm, and at the final height of 36 mm. Solution: Workpiece volume V=75m (502/4)=147,262 mm³. At the moment contact is made by the upper die, h=75 mm and the force F=0. At the start of yielding,/is slightly less than 75 mm, and we assume that strain = 0.002, at which the flow stress is