Impact of axial compression and torque on strain localization and fracture under complex cyclic loading of plexiglas rods

Experimental studies of deformation and fracture of rods made of Plexiglas (PMMA) under complex loading (quasi-static and cyclic torsion under axial compression) are performed. The existence of a range of critical values of axial stress, within which the rod is fractured by the torque, is established. The localization of “frozen” highly elastic strains in constrained cyclic torsion is revealed, and the conditions of its occurrence are determined. The effect of axial stress on strain localization and fracture and the influence of cyclic torsion on the loss of stability of a rod under axial compression are shown.