Question

In a sheet metal of $2$ mm thickness a hole of $10$ mm diameter needs to be punched. The yield strength in tension of the sheet material is $100$ MPa and its ultimate shear strength is $80$ MPa. The force required to punch the hole (in kN) is

Answer 1

Punching force, $F_{max}=\pi dt{\tau }_{pers}$
$=\pi \times 10\times 2\times 80$ =5.024 kN