4,266 research outputs found

    Accumulation of Deformation in the Winding Circuit

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    The formulas and an approximate analysis of the results of the accumulation of deformations in the operations of winding the wire into a spiral and unwinding it to its original state are given. The results of the experiment on winding a thin silver wire on the mandrel and unwinding it to its initial state are presented. The experiments on stretching the wire took place before and after the loading. It was revealed that under the test conditions the notional yield limit increases abruptly, relative elongation is reduced and tensile strength changes slightly. Comparison of load-extension diagrams before and after testing is given as well.     Keywords: wire, hardening, silver, stretching, winding, deformation, stress, mechanical properties

    Finite element modeling of the upsetting of an anisotropic cylindrical workpiece

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    Anisotropic material deformation is modeled with the application of the finite element method. Hill's yield criterion is used for simplified conditions of the upsetting process. The largest flow stress direction is determined to be parallel to all the three coordinate axes by turns. It is discovered that the base of the cylinder can take an oval shape when the flow stress directions of various values lie in the base plane. In this case, the smaller axis of the oval corresponds to the largest flow stress direction. When the flow stress directions of various values lie in the longitudinal section plane of the workpiece, its shape remains cylindrical. The deformation load is higher in this case. © 2017 Author(s)

    Interaction of the Church and Society in Commemoration Campaigns Activated By Museum of Sanctity and Asceticism in the Urals in 20

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    The article analyzes attempts of the Orthodox Church and secular society to form some integrated space of historical memory about repressions in the Urals in the 2

    Development of a procedure for substantiating replacement terms for the condenser tubes of steam turbine installations

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    Results obtained from elaboration of a procedure for estimating replacement terms for the condenser tube systems of steam turbine installations are presented. Censored data processing methods are used in performing statistical assessment of replacement terms. The service life of condenser tubes blanked off in the course of turbine operation is assumed to be known (complete operation time), and that for tubes blanked off during the turbine repair process is assumed to be undetermined (censored operation time). The criterion for estimating the replacement term for a condenser tube system is defined as the ratio between the number of tubes blanked off during a repair and in the course of turbine operation. The procedure is validated by the results from a study on analyzing the damageability of tubes made of different materials for the condensers of 11 turbines with capacities ranging from 25 to 500 MW. © 2013 Pleiades Publishing, Ltd

    The properties of coke breeze briquettes produced by ram briquetting

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    The paper reports on the results of briquetting coke breeze with a binder in a closed cylindrical press-die. Liquid glass is used as a binder. Approximating curves for the "compaction ratio vs. compaction pressure" dependences are plotted from experimental data. The mechanical properties of the briquettes are determined, namely, drop damage resistance and breaking stress. The results are presented as approximating dependences in the form of a power function. © 2017 Author(s)

    Evolution of surface defects in platinum alloy wire under drawing

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    The shape and chemical composition of particles polluting the surface of ultrafine wire made of the platinum Pt92.5Pd4Rh3.5 alloy has been revealed by electron microscopy and microspectral analysis. The phenomenon of the appearance of pores in the particles, which are elongated in the direction of drawing, has been discovered. The problem of calculating the stress-strain state is stated by the finite element method. After solving the problem, it is demonstrated that the appearance of additional defects is related to the proportion of stresses in the scheme of metal forming by drawing. © 2017 Author(s).The work was done within the State Task, theme No. 01201375904, and financially supported by the RF Government, No. 211 (contract No. 02.A03.21.0006)

    Briquette compacting in container with a small taper angle

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    The aim of the study is to determine the strain state of a briquette during the compacting process. Modeling is performed with the use of a software system for the compaction process. Gurson's yield condition for a plastically compressible continuum is applied. A comparison of the known experimental data is made, and it shows good qualitative convergence results. © 2018 Author(s)

    Anisotropy of additively manufactured Ti-6-4 lattice structure

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    Selective laser melting (SLM) is an additive manufacturing technique, where several aspects resulting in the anisotropy of properties is combined. This study provides an analysis of selective laser melting of the diamond lattice structure of Ti-6Al-4 in terms of anisotropy of Vickers microhardness depending on the location and direction of indentation. A statistical review of microhardness values is presented. © 2019 Author(s)
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