Tilda Publishing

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Tilda Publishing

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

2024, No. 4, CONTENTS

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Tilda Publishing

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

2024, No. 4, ABSTRACTS

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Microstructure and physico-mechanical properties of steel, processed by a pulsed electron beam

N. I. Poliak, V. M. Anishchik

Belarusian State University, 4 Nezavisimosti Avenue, 220030 Minsk, Belarus
E-mail: n.poliak@mail.ru; anishchik@mail.ru

The effect of processing with 1 and 20 pulses of an electron beam with energy E = 300 keV, current density J = 3 A/cm2 and pulse duration τ = 50 ns on carbon steel surface condition is investigated. It is shown that surface treatment with a pulsed electron beam leads to significant changes in its morphology, increasing with an increase in the number of pulses, the appearance of new phases and, as a result, changes in the parameters of the fine structure (the lattice parameter, microstresses, the size of mosaic blocks) and physico-mechanical properties.

Keywords: pulsed electron beam, steel, microstructure, phase composition, instrumented indentation test, hardness, elastoplastic characteristics.

DOI: 10.30791/0015-3214-2024-4-5-15

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Irradiation modes and phase explosion during ablation
of steel targets with a scanning beam of pulsed radiation
of a nanosecond duration Yb:YAG laser

S. B. Mikhailov¹, S. G. Gorny¹, N. V. Zhukov<sup>2

1</sup> LLC “Laser Center”, 22 Marshal Tukhachevsky st., 195176 Saint Petersburg, Russia
E-mail: msk@newlaser.ru; SGorny@newlaser.ru
² Prokhorov General Physics Institute of the Russian Academy of Sciences, 38 Vavilova st., 119991 Moscow GSP-1, Russia
E-mail: souler177@gmail.com

The results of experiments on ablation of several grades steel targets — high-carbon steel (97 % Fe, 1.3 % C), low-carbon steel (97 % Fe, 0.3 % C) and stainless steel AISI 304, scanning beam of nanosecond laser pulse are given. The dependence of ablation depth ∆h and ablation energy efficiency ηE on intensity in the range q = 2·108 – 7·108 W/cm2 has been determined. It has been established, that during carbon steels targets ablation the mechanism of explosive boiling (phase explosion) is realized, for characterization of which the concept of “explosion force” Pe is introduced. The Pe value is the ratio of the change in the target material volume having removed ΔV to the pulse energy ΔE at the point of the Dh(q) dependency curve with the maximum rate of ablation depth growth. The values Pe are given, calculated according to graphs Dh(q), as well as the values determined according to published data for various materials (Al, Si, Ni). The range of the values of “explosion force” is Pe = (1.35 – 30)·106 mm3/J, i. e. the maximum and minimum values differ by more than an order of magnitude, with Pe values calculated for a given material depending on the duration of tp pulse, which seems to be with the penetration depth of the thermal wave deep into the target material. As for the results of our experiments, in high-carbon steel target irradiation, Pe values are only slightly lower than the maximum values obtained when irradiating Al and Si targets, and for low-carbon steel — close to the minimum values. The dependence of ablation depth on the pulse interval is determined. It has been established that the nature of the curve of this relationship is determined by the change in the concentration of micro- and nanoparticles, which are formed by the action of previous laser pulses and absorb the energy of the laser pulse having irradiated.

Key words: laser ablation, steel ablation, ablation efficiency, phase explosion, pulse interval.

DOI: 10.30791/0015-3214-2024-4-16-25

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Oxidation processes on the surface of the laser treatment zone of tool steels

A. T. Kozakov¹, S. I. Yaresko², A. V. Sidashov<sup>3

1</sup> Research Institute of Physics of South Federal University,
194 Prospect Stachki, 344091 Rostov-on-Don, Russia
E-mail: kozakov_a@mail.ru
² Samara Branch of P.N. Lebedev Physical Institute of the Russian Academy of Sciences,
221, Novo-Sadovaya, 443011, Samara, Russia
E-mail: yarsi54@gmail.com
³ Rostov State Transport University,
2 Rostovskogo Strelkovogo Polka Narodnogo Opolcheniya Sq., 344038, Rostov-on-Don, Russia
E-mail: iav-1980@yandex.ru

The results of a study of the composition of oxides formed on the surface of the laser exposure zone (LEZ) in the air of tool steels differing in chemical composition and degree of alloying are presened. 150Cr14 (9XC), M2 (R6M5) and T8 (R9K5) steels were used as the object of research. It was established by XPS that the formed oxide films have a qualitatively matching “layered” structure and differ significantly from each other, both in total thickness and in the thicknesses of the oxide films of different phase composition included in them. It was shown, that the formed film is essentially multilayered and multicomponent. For alloyed tool steels, a significant redistribution of the concentrations of alloying elements by the depth of the LEZ was established, which determines the composition of the formed oxides and their location relative to the base material. It was shown that, regardless of the composition of the steel, the external layer of the oxide film on the surface of the LEZ consists mainly of a mixture of FeO and Fe2O3 oxides. Fe3O4 oxide and a mixture of higher oxides of alloying elements, which are located in the following sequence deep from the surface of the zone: WO3, V2O5, MoO2, Cr2O3 and CoO are located deeper to the base metal. Selective enrichment of the surface with W and Mo atoms was found for T8 steel, leading to hardening of the grain boundaries and the appearance of a local hardened layer at a depth of 90 nm. According to the research data, it was concluded that the integral thickness of the oxide film on the surface of the studied steels does not exceed 200 – 250 nm.

Keywords: laser treatment, tool steels, surface, oxide film, XPS, elemental composition, phase composition.

DOI: 10.30791/0015-3214-2024-4-26-39

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Analysis of plastic deformation by the method of inverse problems

T. V. Brovman

Tver State Technical University, 22 Af. Nikitin embankment, 170026 Tver, Russia
E-mail: brovman@mail.ru

The non-stationary metal flow during rolling of the front and rear ends of the strip is investigated, which is important for analyzing the conditions of gripping the workpiece by the rolls and the correct profiling of its end surfaces, ensuring a decrease in metal losses due to trimming. During rolling, the surface layers receive a higher elongation than the central ones, and the ends of the workpieces acquire a concave shape, as a result of which they have to be cut off. To reduce the elongation of the surface layers, the front end of the strip must be rolled under conditions when the workpiece moves faster than the rolls. Calculations of inverse problems at the final specified positions of the deformable medium make it possible to restore the initial profile of the workpiece from the specified final one.
Keywords: plasticity, billet ends, inverse problem.

DOI: 10.30791/0015-3214-2024-4-40-46

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Methodological aspects of determining the surface tension
of mineral powder systems using compacts

V. E. Danilov¹, A. M. Aisenstadt¹, E. V. Korolev², A. V.Shamanina¹, G. A. Garamov<sup>1

1</sup> Northern (Arctic) Federal University named after M.V. Lomonosov,
17 Severnaya Dvina Emb., 163002 Arkhangelsk, Russia
E-mail: v.danilov@narfu.ru; a.isenshtadt@narfu.ru; alexandra.shamanina@yandex.ru; georgiigaramov1997@gmail.com
² Saint Petersburg State University of Architecture and Civil Engineering,
4, 2-nd Krasnoarmeiskaya Str., 190005 St Petersburg, Russia
E-mail: prorector_nr@spbgasu.ru

The article considers methodological aspects of using compacts (pressed samples) to study surface tension, wetting, and a number of other important colloidal-chemical properties of polymineral powders, including those subjected to mechanical activation. The effect of changes occurring with materials during pressing is investigated, and recommendations are developed for making pressed samples to measure surface tension. Compacts from mechanically activated quartz-containing polymineral powder of varying degrees of dispersion were made by pressing under pressure from 15.9 to 707.4 MPa. Surface tension (polar and dispersion components), color coordinates, and strength properties were determined for the obtained samples. It is shown that there are functional dependencies between the characteristics under consideration and the duration of grinding, as well as the pressing pressure. For the first time, the nature of changes in the polar component of the surface tension of mineral powders during their mechanical activation and pressing (compact production) was established. A feature of pressing finely dispersed powders has been revealed, consisting in a decrease in the values of the surface tension indicator (due to a denser packing of particles in samples and, as a result, the formation of a large number of Van der Waals bonds), while for coarsely dispersed powders an increase in its values is observed due to the crushing of brittle grains of minerals and, as a result, the formation of new active centers occurs. Based on the determination of the surface tension of mineral powder systems using compacts, recommendations have been developed for their manufacture to avoid possible errors in measuring the surface tension of the original mineral powders.

Keywords: polymineral powders, polydispersed powders, compacts, surface tension, Van der Waals connections, crushing grains of minerals, formation of active centers.

DOI: 10.30791/0015-3214-2024-4-47-64

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Extraction of platinum from silicate melt in a direct current ore-thermal furnace

A. A. Nikolaev, S. M. Muromsky, O. A. Ovchinnikova, T. N. Penkina

Baykov Institute of Metallurgy and Materials Science of the Russian Academy of Sciences (IMET RAS),
49 Leninsky prospect, 119334 Moscow, Russia
E-mail: anikolaev@imet.ac.ru

The pyrometallurgical extraction of platinum from an oxide system based on SiO2, Al2O3 and CaO has been experimentally studied. This material was an unclaimed waste of the glass industry with a platinum content of 0.03 %. The material was subjected to reduction melting in a laboratory DC ore-thermal furnace. The furnace had a graphite crucible with a volume of 10 dm3 with an axially mounted graphite electrode. The crucible had a magnesite lining and was placed in a steel casing. A negative potential was applied to the electrode from the power supply, and a positive potential was applied to the crucible. The melting was carried out at a current of 300 A and a voltage of 100 V. The material was loaded during the melting process as it melted. A flux based on CaO and SiO2 was added to the material to reduce the melting point. The melt had a temperature of 1850 K in this case. 41.6 kg of the charge was remelted for 6.5 hours with an intermediate drain of the melt. The melt was drained partly by tilting the crucible, leaving the metal phase at the bottom. The metal phase weighed 322 g. It was ferrosilicon containing ≈ 20 % Si and 1.44 % Pt. The energy and material balances of melting were considered. The microstructure of both the initial material and the products of melting were studied. Platinum is contained in the starting material in the form of inclusions with a size of about 10 mm. The inclusions were deposited on the bottom of the crucible when the material was melted and were extracted with ferrosilicon, formed as a result of carbon thermal reduction. It was shown that the Stokes law is applicable to determine the deposition rate under electric melting conditions. Platinum and copper form separate phases when ferrosilicon solidifies. The platinum content is about 50 % in these phases.

Key words: platinum, extraction, waste, oxides, melt.

DOI: 10.30791/0015-3214-2024-4-65-71

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Combination of methods of self-propagating high-temperature synthesis and infiltration to obtain W – Cu pseudo-alloy

V. Yu. Barinov¹, S. S. Мanokhin², Yu. R. Kolobov<sup>2

1</sup> Merzhanov Institute of Structural Macrokinetics and Materials Science of Russian Academy of Sciences,
8 Academician Osipyan str., 142432 Chernogolovka, Moscow Region, Russia
E-mail: barinov@ism.ac.ru
² Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry, Russian Academy of Sciences,
1 Academician Semenov avenue, 142432 Chernogolovka, Moscow Region, Russia
E-mail: manohin@bk.ru; kolobov@icp.ac.ru

The possibility of obtaining a tungsten-copper pseudo-alloy by the infiltration method using a highly exotemic combustion reaction of silicon in nitrogen as a heating source has been studied. Due to the heat released as a result of combustion, the porous tungsten frame was impregnated with molten copper. Samples of the resulting pseudo-alloys had a relative density of 0.9.

Key words: self-propagating high-temperature synthesis, pseudo-alloy, tungsten, copper, infiltration, combustion, silicon, nitrogen.

DOI: 10.30791/0015-3214-2024-4-72-76

ПЕРСПЕКТИВНЫЕ МАТЕРИАЛЫ

Study of shrinkage of crystallizing metal under controlled pressure application

V. F. Korostelev¹, M. S. Denisov<sup>2, 1

1</sup> Institute of Mechanical Engineering and Automobile Transport of Vladimir State University named after Alexander Grigorievich
and Nikolay Grigorievich Stoletov, 87 Gorky str., 600000 Vladimir, Russia
E-mail: korostelev@vlsu.ru
² Vladimir State University named after Alexander Grigorievich and Nikolay Grigorievich Stoletov (VlSU),
7 Gorky str., 600000 Vladimir, Russia
E-mail: denisovmaxim90@mail.ru

One of the promising technological processes aimed at expanding the scope of application of deformable heat-treated high-strength aluminum-based alloys such as D16, B95, etc. is liquid stamping — crystallization under pressure. In the process of liquid stamping, defects of gas-shrinkage origin and liquation occur in sections with a thickness of more than 40 mm, which cannot be eliminated by known methods. As an approach to solving this problem, it is proposed to use the dependence of the change in the volume of the crystallizing metal on the pressure value. It is established that the metal property hidden from the known methods of studying the crystallization process, referred to in this work by the term “compactness of the crystallizing metal” can be up to 5 – 6 % of the total volume of the metal. An original research methodology is proposed, controlled and controlled process parameters are determined to ensure the formation of a structure without defects. Using the example of the production of molds for casting plastic parts, the advantages of the proposed casting process with the imposition of pressure on the crystallizing metal are shown.

Keywords: liquid stamping, metal pressing into the interdendritic cavities, control and control of pressure, volumetric and directional crystallization, density, hardness and strength of the metal.