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., Yead of the Dept. of Materials Forming and Additive Technologies, e-mail: dengnevashev@mail.ru
Le Trung Dung, 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 influence of uniformity in determining deformation was studied when the hardening curve is constructed during uniaxial compression of the sample. In the process of shaping, testing samples for uniaxial compression, and constructing a hardening curve, local phenomena were determined, including the uniformity of the effect of hardness changes over load fields. The influence of the uniformity of determining the amount of deformation on the accuracy of constructing the hardening curve under uniaxial compression based on the results of determining the deformation and hardness along the section along the axis of the deposited metal sample has been investigated and established. Graphs of the dependence of the hardness of deformation along the flow field along the section along the axis of the deposited metal sample at various degrees of precipitation of cylindrical samples for steel 10 GOST 10702–86 are constructed. Thus, it is possible to predict the properties of parts obtained by cold volumetric stamping methods using a hardening curve. To assess the accuracy in determining the intensity of deformation and plotting the hardening schedule, experiments were conducted on uniaxial compression of samples from the metal under study. To reduce the effect of the friction force on the contact surface of the punch with the sample surface, polyethylene film gaskets were used at the ends of the sample in combination with engine oil, while the stress state can be considered linear. The initial data and the results of the study are presented.

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