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Two devices intended for copper cylindrical liner gasdynamic acceleration to velocities of 5–7 km/s using the chemicals explosion energy have been investigated. It has been demonstrated that the acceleration of quasi-isentropically and isentropically loaded liners under the conditions of high-level dynamics, symmetry of deposition, and suppression of shock-induced dusting is feasible.

In this paper, electrochemical impedance responses of subdiffusive phase transition materials are calculated and analyzed for one-dimensional cell with reflecting and absorbing boundary conditions. The description is based on the generalization of the diffusive Warburg impedance within the fractional phase field approach utilizing the time-fractional Cahn–Hilliard equation. The driving force in the model is the chemical potential of ions, that is described in terms of the phase field allowing us to avoid additional calculation of the activity coefficient. The derived impedance spectra are applied to describe the response of supercapacitors with polyaniline/carbon nanotube electrodes.

Pseudo-capacitors with electrodes based on polyaniline and vertically aligned multiwalled carbon nanotubes (PANI/VA-MWCNT) composite are studied. Fractional differential models of supercapacitors are briefly discussed. The appropriate fractional circuit model for PANI/MWCNT pseudo-capacitors is found to be a linearized version of the recently proposed phase-field diffusion model based on the fractional Cahn–Hilliard equation. The temperature dependencies of the model parameters are determined by means of impedance spectroscopy. The fractional-order α is weakly sensitive to temperature, and the fractional dynamic behavior is related to the pore morphology rather than to thermally activated ion-hopping in PANI/MWCNT composite.

The features of methods for constructing recrystallization curves of the second and third kind and the dependence “average grain size (area) - strain intensity – temperature” are given. For alloys of various structural classes VZH159 and 14Cr17Ni2 using the above methods, a recrystallization curve and the recrystallization dependence for a temperature of 1100℃ are constructed. The advantages and disadvantages of the above methods are considered.

A trend in the development of modern electroslag remelting is the use of the ESR technology with replaceable consumable electrodes during melting and protection of smelting space by an inert gas in a cyclic electroslag remelting (CESR) regime. Industrial development of this technology at domestic enterprises is at an initial stage, and many questions related to features of remelting of high-alloy steels and alloys have not been studied practically. Information presented in this article reflects results of studying the CESR process in a model furnace EShP-0.5U of RPA TsNIITMASh and industrial smelting in the EShP-9.8 furnace of Ruspolimet.

The technologies that are used to make hollow ingots are analyzed. Their characteristic features are discussed along with their intrinsic advantages and disadvantages. A new technology that significantly alleviates the formation of defective regions in hollow ingots during their crystallization is proposed.

This is the second article on a method developed by TsNIITMASh to design forging ingots. The method makes it possible to eliminate axial porosity in the body of the ingot. Results are presented from a comparison of calculated data and experimental data obtained on the basis of the new method. It is shown that the calculated results agree satisfactorily with the experimental results.

method is proposed for calculating the geometric and technological parameters for the casting of forging ingots – including large ingots – without axial shrinkage defects. It is shown that axial porosity can be eliminated by observing two conditions: 1) the conicity of the ingot mold should be sufficient to ensure directional solidification of the ingot and should have values of 1.5–2.0 % for H/D ≤ 1.0 and 14.5–16.0 % for larger values of H/D; 2) the parameters of the hot top, its thermal insulation, and the temperature-rate regimes used for casting should ensure that a sufficient quantity of molten metal is continuously supplied to the solidifying ingot during the entire time that it is being formed. It is recommended that outdated norms for the design of large forging ingots (in the standard OST 108.962.02-85) be revised. Ingots cast in accordance with these norms do not satisfy modern quality requirements.

This is the third and final article on a method developed by TsNIITMASh to design forging ingots so as to prevent the formation of an axial shrinkage cavity in the body of the ingot. Theoretical and experimental results from use of the method and factory-designed casting equipment to obtain such ingots are compared together with requirements of the standard OST 108.962.02-85. It is shown that the theoretical and experimental results agree satisfactorily with one another .