Evaluation the Applicability of the New Torsion Testing Method to Study the Rheological Properties of Materials in a Cold State

Abstract

The most important parameter characterizing the rheological properties of steels and alloys is the strain resistance. The new method of testing cylindrical specimens for torsion with variable grip’s acceleration proposed (application No. 2018132149 of 07.09.2018 for the patent of the Russian Federation for the invention). This method is designed to study the rheological properties of steels and alloys mainly in a hot state. However, this method is universal and can be used to determine strain resistance of materials in a cold state. The article is devoted to the applicability evaluation of the proposed torsion testing method to study the rheological properties of materials in a cold state. It’s done on a basis of the comparison of the hardening curves obtained during the testing of specimens for tensile and torsion. The CrWMn steel was used. The results show that the hardening curves obtained during the torsion and tensile tests are close, and the yield stress values differ by about 3%. It can be assumed that the developed method of torsion testing allows to obtain reliable values of the material’s strain resistance in a cold state.


 


 


Keywords: hardening curves, strain resistance, torsion test, tensile test, test control, post-processing, experimental laboratory setup

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