OCTAHEDRAL SHEARING STRESS THEORY

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OCTAHEDRAL SHEARING STRESS THEORY

          
           According to this theory, the critical quantity is the shearing stress on the octahedral plane. The plane which is equally inclined to all the three principle axes is called the octahedral plane.



τoct = (1/3) [(σ1 – σ2)2 + (σ2 – σ3)2 + (σ3 – σ1)2]1/2

                                                                                       where, τoct = octahedral shearing stress

Failure is said to occur when τoct = ((√2)/3) σe


           This theory holds feasible for ductile materials and is similar to Von Mises theory.

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