A square bar, 5 mm X 5 mm in cross section and 100 mm long is to be flattened into a section that is only 2 mm thick and remains 100 mm in length. The press velocity is 2 dmin. The coefficient of friction is 0.10, with a lubricant. The value for K is 620 MPa, and IZ is 0.18. The value of C is 120 MPa and m is 0.10 at 1000°C.
a. Make a sketch of the bar before and after deformation.
b. What is the engineering strain in the height direction?
c. What is the true strain in the height direction?
d. What is the true strain rate?
e. What is the pressure-multiplying factor?
f. What is the mean flow stress (MPa)?
g. What is the flow stress if the part is formed at 1000°C (MPa)?
h. What is the force required (newtons) if the part is formed at IOOO"C? (b. -0.6 c. -0.916 d. 16.67 sec-' e. 1.312 f. 517 MPa g. 158.5 MPa h. 260 kN (259,500 N))