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A method for studying microplasticity using a mechanical relaxometer

August 1999
Industrial Laboratory 65(8):518-520

Authors:

A method for studying microplasticity of metallic materials based on in situ measurement of internal friction at low sonic frequencies (f similar to 100 Hz) is described. The method uses a relaxometer consisting of a torsional pendulum and a reversible twisting device with a Pi-shaped grip, which allows one to induce strain in relatively thick specimens of diameter to 3 - 4 mm and to measure the residual strain gamma(r) after a cycle of alternating torsion and half-cycles of repeated (of the same sign) torsion.

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