Determination of the disturbing load required for the compaction of metal powder
DOI:
https://doi.org/10.37142/2076-2151/2025-1(54)54Keywords:
rheological model, metal powder, stress, deformation, amplitude of oscillations.Abstract
Savielov D., Kulynych S. Determination of the disturbing load required for the compaction of metal powder
The main goal of these studies is to determine the amplitude of vibrations of the working body and the corresponding vibration load necessary for the compaction of metal powders. On the basis of a thorough analysis of the scientific and technical literature, it was established that today, for the production of products from metal powders, the technology of vibration compaction of metal powders is used, which does not take into account the specific features and properties of the powder mixture and does not allow obtaining high-quality and reliable powder products from it. Based on the analysis of the behavior of materials and existing rheological models of compacted media, it was determined that a generalized rheological model is proposed for a dispersed mixture of metal powder that is subject to vibration, in which internal friction is taken into account under the action of an external load. It was established that in the existing studies, the rheological model was not used to describe the behavior of the polymer concrete mixture as a continuous medium, and its oscillations, under the influence of vibration, were not described by the wave equation of oscillations. For the proposed rheological model of compacting polymer concrete mixture, which takes into account its elastic, viscous and plastic properties, a wave equation of oscillations was developed, for the theoretical analysis of which the solution method in complex functions was applied. As a result of the conducted theoretical studies, the phase speed of excitation propagation and the absorption coefficient, which characterizes the decrease of excitation when moving away from the source of excitation, were determined, the solution of the wave equation of oscillations was found, and analytical expressions were derived for determining the amplitude stress that occurs on the surface and at the base of the compacted layer of polymer concrete depending on from the coordinate. On the basis of the condition that describes compaction, an analytical expression was obtained for determining the excitation amplitude of the polymer concrete surface, which is necessary for its complete compaction. Based on the determined value of the excitation amplitude, the amplitude value of the excitation force of the vibrators for equipping the vibrating working body with them is determined.
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