KSHP. OMD №2-2026
A. E. Senner, N. M. Smagin (Dubna State University, Dubna)
Negative spring in sheet stamping
The paper considers the phenomenon of negative angular springing that occurs when calibrating parts with obtuse angles in sheet stamping processes. The results of an experimental study of the calibration of parts made of electrotechnical non-alloy steel are presented. It is shown that when performing the calibration operation, there is a steady decrease in the angle of the part, after removing the load, compared with the angle of the tool. It has been established that the cause of negative springing is the material being compressed in the area of the bending radius and the formation of residual compressive stresses in the inner layers of the sheet. The results obtained can be used in the design of calibration operations and refinement of geometric parameters of die tooling.
Keywords: sheet stamping, metal springing, negative springing, calibration.
A. L. Vorontsov, D. A. Lebedeva (Bauman Moscow State Technical University, Moscow)
Investigation of backward-and-forward extrusion of tumblers with a co-bottom part.
Part 27. Experimental verification of theoretical formulas in traditional extrusion with temperature effect
This paper examines the cold, constrained extrusion of cups with a conical bottom from a hardening material. Methods for performing specific calculations of the deforming force for various extrusion geometric parameters with a temperature effect are demonstrated in detail. A comparison with experimental data obtained during the extrusion of L63 brass and 12Kh18N9T steel demonstrates the high accuracy of the derived calculation formulas.
Keywords: die forging; metal cup with a conical bottom; combined extrusion; stress; deformation.
A. I. Kanareykin (Russian State University for Geological Prospecting (MGRI), Moscow)
The first stochastic longevity model
The article is devoted to the stochastic longevity model. The stochastic durability model is a model that takes into account the probabilistic nature of the process when assessing the durability of objects, elements, structures and structures. Unlike deterministic models, stochastic models take into account uncertainty and allow us to estimate the probability distribution of possible outcomes. Stochastic modeling itself is based on mathematical statistics and probability theory. The obtained model makes it possible to determine from the experiment on long-term durability a specifi c type of stochastic kinetic differential equation of durability.
Keywords: durability; stochastic durability model; statistical series; durability distribution law.
A. I. Kanareykin (Russian State University for Geological Prospecting (MGRI), Moscow)
Heating of an infinite rod by a point source
The article is devoted to the theoretical issues of heat transfer through a rod. The paper considers the process of heating an infinite rod by a point source. Therefore, the process under consideration is non-stationary. The solution to the problem is given using Green's functions in the standard form. The obtained result can be applied when calculating the heat transfer of cylindrical shaped parts.
Keywords: core; heating; thermal conductivity; nonstationary; Green's function.
L. B. Aksenov, A. M. Zolotov, V. S. Mamutov, V. A. Lobov, E. O. Frolova (Peter the Great St. Petersburg Polytechnic University, St. Petersburg)
Prediction of non-uniform hardening during flange stamping by inner draw
This paper examines a method for producing flange parts using a drawing process with wall thinning along the inner contour. Computer modeling demonstrates the formation of significant non-uniformity in the degree of deformation during stamping. Mathematical models for predicting this heterogeneity are proposed. Based on the conducted research, a manufacturing technology for a gas turbine engine combustion chamber flange is developed.
Keywords: drawing with thinning; flanged sleeve; degree of deformation; heterogeneity; hardness.
A. E. Senner, N. M. Smagin (Dubna State University, Dubna)
Application of reversible bending in sheet stamping processes
The article presents the technology of manufacturing pipe blanks from sheet metal using two-operation reversible bending. Bending refers to metalworking operations by pressure. The principle of forming a pipe billet by sequential bending is described. A method for calculating the geometry of a working die tool is proposed, taking into account the springs and characteristics of metals. The advantages and features of the technology and this approach as a whole are indicated.
Keywords: metal pressure treatment; sheet stamping; reversible bending; pipe billet.
V. I. Erofeev, A. I. Ermolaev, S. N. Okhulkov (Mechanical Engineering Research Institute of RAS, Nizhny Novgorod); A. S. Plekhov (Lobachevsky University, Nizhny Novgorod)
Hydraulic loader for hot crank stamping press equipped with magnetorheological mount (part 1)
The paper proposes a solution to the urgent problem of checking hot crank stamping presses (HCSP) when loading the ram with a specified force. Currently, in HCSP, the control and calibration of the press force is carried out by strain gauge sensors (strain gauges). For this purpose, strain gauges are glued to the press parts subject to the greatest deformation (ram, tie rods, frame, etc.). Also, in the practice of operating HCSP, the verification of the press loading is carried out using strain gauges calibrated by a hydraulic loader. The hydraulic press loader is designed to verify the presses when loading the ram with a specified force at a small stroke of the ram, at the last stage of pressing during stamping. Strain gauges are glued to the spacers of the hydraulic loader. The paper presents studies on upgrading the HCSP hydraulic loader with a spacer made on the basis of a self-healing fuse with an elastic force converter and a magnetorheological hydraulic mount. A method and means are proposed for upgrading the HCSP hydraulic loader on the basis of magnetorheological hydraulic mounts instead of strain gauges, allowing for real-time verification of the loading process in the press.
Keywords: crank hot stamping press; strain gauge sensors; hydraulic loader equipped with spacers; self-restoring fuse with elastic force converter; magnetorheological hydraulic mount.
S. S. Chuikov (Industrial University of Tyumen, Tyumen); R. S. Chuikov (Industrial University of Tyumen, Tyumen; Moscow University «Synergy», Moscow)
Influence of internal stresses on tool hard alloys of the TK group
The article is devoted to analyzing the nature of internal stresses in TK-group tool cemented carbides and their influence on the mechanical, performance, and thermal stability properties of cutting tools. Particular attention is given to the combined use of theoretical models, experimental data, and visualization in the form of diagrams. The work explains the mechanisms of thermally and technologically induced residual stresses, evaluates their distribution within the multicomponent structure, and provides recommendations for reducing the level of internal stresses.
Keywords: TK-group cemented carbides; residual stresses; TiC–Co; TiC–Ni–Mo; wear resistance; stress–strain state; intrinsic stresses.
S. S. Chuikov (Industrial University of Tyumen, Tyumen); R. S. Chuikov (Industrial University of Tyumen, Tyumen; Moscow University «Synergy», Moscow)
Methods of control of internal stresses in tool hard alloys of the TK group
The article presents modern approaches to the control and analysis of residual internal stresses in TK-group cemented carbides (TiC–Co,). Contact, non-contact, destructive, and non-destructive diagnostic methods are examined, including X-ray–based techniques, digital optical methods, ultrasonic testing, computed tomography, and local microprobe analysis. An extended finite element analysis (FEA) model is introduced, accounting for porosity, local anisotropy, heterogeneity of TiC grain size, thermomechanical effects, and temperature gradients. Correlation between simulation results and experimental diagnostic methods is provided, enabling a comprehensive multilevel approach to assessing the stress–strain state of TK-group cemented carbides.
Keywords: TK-group cemented carbides; internal stresses; TiC–Co; X-ray methods; ultrasonic testing; computed tomography; DIC; porosity; thermomechanical effects; FEA modeling.