Математичне моделювання напружено-деформованого стану металу при нанесенні концентратора напружень клиновим інструментом

Serhii Karnaukh

doi:10.20535/2521-1943.2026.10.2(109).356682

Authors

Serhii Karnaukh Donbass State Engineering Academy, Ukraine https://orcid.org/0000-0003-2878-4065

DOI:

https://doi.org/10.20535/2521-1943.2026.10.2(109).356682

Keywords:

wedge tool, stress concentrator, cold fracture, Обрані:stress-strain state, technological force

Abstract

The scientific article addresses the problem of improving the efficiency of sectional rolled product separation processes by enhancing the methods of stress concentrator formation during cold bending fracture. The relevance of the study is driven by the need to reduce energy-force expenditures, improve workpiece quality, and implement waste-free technologies in metallurgical production. The aim of the work is to optimize the parameters of the wedge tool indentation process based on an analysis of the stress‑strain state of the metal. The methodological framework of the study consists of analytical modeling using the slip line field method (Hill’s solution) for a rigid‑plastic medium. An improved algorithm for determining the contact pressure and the technological force, accounting for the geometry of the plastic zone of the displaced metal, is proposed. Special attention is paid to a comparative analysis of two approaches for approximating the free boundary of the plastic region-straight and concave. To verify the adequacy of the analytical relationships, numerical modeling was carried out in the Deform 3D environment, which enabled the investigation of the influence of the main technological parameters (wedge angle, indentation depth, loading rate) on the force and energy characteristics of the process. Additionally, experimental studies were performed using a specially designed setup, providing verification of the obtained results. It was established that the use of the model with a concave free boundary of the plastic zone yields a more accurate description of the stress‑strain state of the metal and reduces the calculated wedge indentation force compared to the traditional model. The regularities of the influence of the process parameters were identified: as the wedge angle, indentation depth, and loading rate increase, the force and deformation work rise, and there exists a rational range of their values beyond which a sharp increase in energy consumption occurs. The discrepancies between the analytical, numerical, and experimental results do not exceed acceptable engineering limits. The scientific novelty lies in the development of approaches for describing localized plastic deformation during the formation of stress concentrators and in refining the geometry of the plastic zone. The practical significance of the results lies in their applicability for optimizing wedge tool parameters, improving workpiece quality, and enhancing the efficiency of waste-free rolled product separation technologies.

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