Step 1: Understanding Maximum Shear Stress Theory.
The maximum shear stress failure theory, also known as Tresca's theory, posits that yielding happens when the maximum shear stress attains a critical threshold.The maximum shear stress is determined by:\[\tau_{\text{max}} = \frac{\sigma_1 - \sigma_3}{2}\]Here, \( \sigma_1 \) and \( \sigma_3 \) represent the largest and smallest principal stresses, respectively.Step 2: Relate the theory to yield stress.
Tresca's theory dictates that yielding occurs when:\[\tau_{\text{max}} = \frac{\sigma_{\text{yield}}}{\sqrt{2}}\]Therefore, the solution is:Maximum shear stress = \( \sqrt{2} \times \text{yield stress} \). Final Answer: \[ \boxed{\sqrt{2} \times \text{yield stress}}\]