F = pi * R^2 * delta {(1+2(m)(R))/(3*sqrt(3*T))}
R = Radius of cylinder
T = Thickness
delta = yield strength
m = coefficient of friction
An engineering technology student is attempting to impress his date by demonstrating some of the neat aspects of metalforming. He places a shiny penny between the platens of a 60,000-lb-capacity press and proceeds to apply pressure. Assume the coin has a 3/4 inch diameter and is 1/16 inch thick. The yield strength is estimated at 50,000 psi, and since no lubricant is applied, the friction is that of complete sticking, or m=1.0
1. Compute the force required to induce plastic deformation.
2. If this force is greater that the capacity of the press (60,000 lb), compute the pressure when the full-capacity force of 60,000 lb is applied.
3. If the press surfaces are made from thick plates of steel with a yield strength of 120,000 psi, describe the results of the demonstration.