Moscow Polytechnic University, Moscow, Russia

Yu. K. Filippov, Dr. Eng., Prof., Dept. of Materials Forming and Additive Technologies, e-mail: yulianf@mail.ru
D. A. Gnevashev, Cand. Eng., Associate Prof., Head of Dept. of Materials Forming and Additive Technologies, e-mail: dengnevashev@mail.ru
Le Chung Zung, Postgraduate Student, Dept. of Materials Forming and Additive Technologies, e-mail: sea.lawyer.vn@gmail.com
Doan Xuan Quang, Postgraduate Student, Dept. of Materials Forming and Additive Technologies, e-mail: doanquang1809@gmail.com

The accuracy of constructing the hardening curve during the testing samples under uniaxial compression was studied, depending on the magnitude of deformation. When constructing the hardening curve during the testing of samples under uniaxial compression, local phenomena accompanying the process of form change were determined, including the influence of changes in hardness along the flow field. The accuracy of constructing the hardening curve under uniaxial compression between measurements of the magnitude of metal deformation and hardness during plastic deformation has been studied and established. The change in the deformation magnitude across the sample’s flow field during forming was studied and established when constructing the hardening curve under uniaxial compression during plastic deformation. Graphs were constructed of the dependence of the hardness value on the deformation value along the flow field at various degrees of settlement of cylindrical samples made of steel 10 GOST 10702-86. This makes it possible to predict the properties of parts produced by cold forging using the hardening curve. To assess the accuracy in determining the magnitude of the strain intensity and constructing the hardening graph, experiments were carried out on compression of samples from the investigated metal. The initial data and results of the study are presented.

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