HENCKY & VON MISES THEORY

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MAXIMUM DISTORTION ENERGY THEORY (HENCKY & VON MISES THEORY)


          As per this theory, the failure or yielding occurs at a point in a member when the distortion strain energy (also called shear strain energy) per unit volume in the stressed material reaches the limiting distortion energy (or distortion energy at yield point) per unit volume as determined from a simple tension test. The maximum distortion energy theory for yielding is expressed as:-

                                               (σ1 – σ2)2 + (σ2 – σ3)2 + (σ3 – σ1)2 = 2σe2
                                                                                                       

          This theory is mostly used for ductile materials in place of maximum strain energy theory. The maximum distortion energy is the difference between the total strain energy and the strain energy due to uniform stress. 


         This theory is also known as Hencky and Von mises theory.

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