Torsion entropic component

We see that the relative change of entropy and internal energy at constant pressure is independent of the degree of twisting. This conclusion differs from that obtained for simple extension or compression. The entropic and energetic components in torsion are identical with the result for simple deformation. Equations (60) and (61) lead to the conclusion that there can be no thermomechanical inversions of heat and internal energy in torsion. 

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