Thefrictional shear stress ($$\tau$$) in metal forming is expressed as
where ‘m’is the friction shear factor and ‘$$\overline{\sigma}$$’ is the flow stress

A

$$\frac{m \overline{\sigma}}{\sqrt{3}}$$

B

$$\frac{\overline{\sigma}}{\sqrt{3m}}$$

C

$$\frac{\overline{\sigma}}{m \sqrt{3}}$$

D

$$\frac{\sqrt{3}}{m}\overline{\sigma}$$