Frontier Materials & Technologies
Peer-reviewed scholarly journal published quarterly since 2008.
Publisher & Founder
Togliatti State University, Togliatti, Russia
WEB: https://www.tltsu.ru/en
Editor-in-Chief
Mikhail M. Krishtal
Doctor of Physical and Mathematical Sciences, Professor
Scopus ResearcherID ORCID
About
Languages: Russian, English. Since 2023, all the articles are published in parallel Russian and English.
Periodicity: quarterly (March 31, June 30, September 30, December 30).
Average time from submission of a manuscript to acceptance for publication: 90 days.
There are no publication fees or fees payable to authors.
The Journal offers authors direct open access to its content.
The journal is included in Scopus (from 2021), CNKI (China National Knowledge Infrastructure), DOAJ (Directory of Open Access Journals).
The journal is included in the List of Peer-reviewed Journals of Higher Attestation Commission, and the research results of a DSc or CSc thesis are recommended to be published in the journal.
For the Russian Science Citation Index, full bibliographic description of all papers are indexed and listed in the Scientific Electronic Library eLIBRARY.RU.
The journal is included in the core of RSCI.
Five-year 2022 Russian Science Citation Index Impact Factor is 0.140 (with no self-citations).
Before December 2021 - Science Vector of Togliatti State University / Vektor nauki Tol'yattinskogo gosudarstvennogo universiteta.
The Subjects for Publishing
The journal publishes original papers in the following areas:
- Mechanical Engineering and Machine Science
- Machine Science (Engineering)
- Friction and Wear in Machines (Engineering)
- Robotics, Mechatronics and Robotical Systems (Engineering)
- Technology and Equipment for Mechanical, Physical and Technical Treatment (Engineering)
- Technologies and Machines for Pressure Treatment (Engineering)
- Welding and Allied Processes and Technologies (Engineering)
- Methods and Devices for Control and Diagnostics of Materials, Goods, Substances and Natural Environment (Engineering)
- Metallurgy and Materials Science
- Physical Metallurgy and Heat Treating of Metals and Alloys(Engineering)
- Metallurgy of Ferrous, Non-Ferrous and Rare Metals (Engineering)
- Pressure Treatment of Metals and Alloys (Engineering)
- Nanotechnologies and Nanomaterials (Physics and Mathematics)
- Materials Science (Engineering)
Current Issue
No 2 (2025)
- Year: 2025
- Published: 30.06.2025
- Articles: 8
- URL: https://vektornaukitech.ru/jour/issue/view/66
The influence of pulse current on drop transfer during double-electrode gas surfacing
Abstract
The application of a circuit with a common pulse current source for surfacing with two electrode wires increases the energy efficiency of the arc process and the welding arc technological properties, but requires a more detailed study of the influence of the mode parameters on its stability. In this regard, this paper focuses on studying the dynamics of formation and transfer of metal drops under various modes of pulsed power supply of the welding arc. Using high-speed video filming of the welding arc and synchronized recording of current and voltage signals, a mode was set (average current value was 250 A, maximum current value in pulse was 600 A, arc voltage was ~30 V), which ensured a stable process of transfer of electrode metal by a drop common to two wires without short circuits. It was found that the common drop under the action of electrodynamic forces acquires centripetal acceleration, which contributes to its directed transfer to the weld pool and allows minimizing the amount of spatter on the surface of the base metal. Using mathematical modeling, the nature of the interaction of welding arcs on two wires was confirmed and it was found that even at the stage of the current pulse “hot” phase (600 A, t=0.8 s), the arc pressure on the plate surface is less than when welding with one wire at direct current. The identified effect is associated with a change in the direction of the plasma flow to perpendicular to the wire axis due to an increase in the electrodynamic attractive force of the magnetic fields around the two wire conductors. Together with a decrease in the arc temperature and pressure on the plate surface during the “heat input control” phase of the current pulse (180 A, t=1.4 s), this should help to reduce the heat input and the depth of penetration of the base metal, and, consequently, reduce the degree of dilution of the deposited alloy by the substrate metal. The latter is especially relevant when solving problems of creating a technology for surfacing of relatively thin layers of corrosion-resistant alloys, in particular, on the surface of petrochemical equipment products.



Effects of extrusion on Young’s modulus and internal friction of magnesium alloys with various long period ordered structure content
Abstract
The relevance of this work stems from the growing interest in magnesium alloys with long period ordered structure (LPSO) due to their unique mechanical properties. Investigating the effect of extrusion on Young’s modulus and internal friction of such alloys provides a deeper understanding of their mechanical behaviour, which is important for the development of new materials with improved performance properties. This research explores the effect of warm extrusion on the structure, dynamic Young’s modulus and internal friction of magnesium alloys containing varying amounts of LPSO phases. Alloys in the Mg–Zn–Y system with estimated LPSO phase contents of 0, 50 and 100 % vol. were analysed using the composite piezoelectric oscillator technique at 100 kHz. The results demonstrate that the Young’s modulus increases with higher LPSO content, driven by the enhanced stiffness and strong interatomic bonding of the LPSO phases. Extrusion leads to a 3 % decrease in Young’s modulus along the direction parallel to its axis for all samples. This effect is explained by the formation of an elongated texture and an increase in the dislocation density. Internal friction measurements revealed a rise in amplitude-independent internal friction post-extrusion, suggesting higher dislocation density, while the critical strain amplitude decreased in alloys with higher LPSO content. Additionally, Young’s modulus softening was reduced after extrusion, primarily due to dislocation-induced hardening. These findings shed light on the mechanical properties of Mg–Zn–Y alloys with LPSO structures, emphasising the effects of extrusion and phase content on their dynamic behaviour.



Ductility, bending and wrapping ability relationship in wires made of electromagnetically cast ultrafine grained Al–0.5Fe and Al–0.5Fe–0.3Cu alloys
Abstract
The research status on such functional properties, as bending capability, wrapping capability and ductility of conductive Al–Fe and Al–Fe–Cu alloys wires is uncertain. Bending and wrapping capability is determined by the industrial standards while no attempts were made to study the relation between them and ductility of the Al alloys wires, paying even less attention to the ultrafine-grained Al-based wires, produced by electromagnetic casting and equal-channel angular pressing. In this study alloys with two different chemical compositions (Al–0.5 wt. % Fe and Al–0.5 wt. % Fe–0.3 wt. % Cu) and two different casting methods (casting into electromagnetic mold and continuous casting and rolling) were used. Part of the wires for the study was prepared by cold drawing (CD), the other part – by the combination of the equal-channel angular pressing by the Conform scheme and cold drawing (ECAP-C+CD) to obtain coarse grained (CG) and ultrafine grained (UFG) structures, respectively. Annealing at 230 °C for 1 h was carried out to evaluate the thermal stability of the wires. It was shown that the correlation between ductility (elongation to failure), number of wraps and number of bends (both before the first crack and before complete failure of the specimen) may differ depending on the deformation value, deformation scheme, and amount of alloying elements of the alloy wire, as well as ability to form solid solutions.



Mechanical and corrosion anisotropy of magnesium single crystal
Abstract
Magnesium and its alloys are promising materials for medical use due to their ability to dissolve safely in the human body. However, the rate of dissolution of bioresorbable implants should be in a narrow enough range. The difficulty in ensuring this condition is that the corrosion process in magnesium alloys is influenced by many factors, including natural (single-crystal) and technological (production scheme) anisotropy. By carrying out technological operations on thermomechanical treatment, it is possible to control the process of formation of the semi-finished product texture and to create artificially a preferred orientation of crystallites in the structure of magnesium alloys and thus control their corrosion resistance. This requires precise knowledge of the relationship between corrosion processes and certain crystallographic directions, which can be most reliably obtained in experiments on single crystals. In this work, mechanical (compression and tension) and corrosion tests were carried out for the first time on the same magnesium single crystal on samples with different crystallographic orientations. The Kearns coefficients calculated from the X-ray diffraction patterns of the single crystal specimen faces by the inverse pole figure method were used as a quantitative criterion of the natural texture. The specimens were subjected to compression tests in the <0001>, <1−100> and <11−20> directions, and to tension tests in the <0001> direction. The specimen surfaces with orientations close to the (0001), (10−10), (2−1−10), and (10−11) crystallographic planes were subjected to corrosion testing. It was found that the Young’s modulus and the Kearns coefficient for the basal and pyramidal faces were 48.6 GPa and 0.81; 45.3 GPa and 0.04, respectively. The shape of the stress curves depended significantly on the sample orientation and was determined by the degree of involvement of various mechanisms in the overall plastic deformation process. The rate of corrosion in a physiological aqueous solution of 0.9 % NaCl on a 72-h basis for the (0001), (10−10), (2−1−10), and (10−11) surfaces was 0.51, 0.76, 0.71 and 0.98 mm/year, respectively. In this case, the (2−1−10) plane experienced only uniform corrosion, the (0001) plane experienced uniform corrosion with minor localised corrosion; the most intense localised corrosion is observed in the (10−10) direction, and the maximum intensity of the combination of localised and uniform corrosion is in the <10−11> direction.



Effect of ultrasonic treatment on structural transformations and mechanical behaviour of amorphous alloys (REVIEW)
Abstract
The wide application of amorphous alloys is complicated by a narrow range of their thermal stability, embrittlement at elevated temperatures, difficult machinability, and low tensile plasticity. Ultrasonic treatment is an innovative method for solving these problems. Integration of ultrasonic technology into the technological chain can contribute to the improvement of the operational property of amorphous alloys, the manufacture of parts from them at different scale levels, and high-quality joining with other materials. The effect of ultrasonic vibrations on structural transformations and mechanical behaviour of amorphous alloys is not completely understood. The lack of an integrated scientific basis for the physical processes and accompanying effects in amorphous alloys under ultrasonic excitation prevents the development of the corresponding technology and optimization of its modes. Over the past decade, researchers have proposed various methods of ultrasonic treatment of amorphous alloys to improve their formability, achieve a balance of plasticity and strength, and consolidate with each other and with metals. In addition, certain ideas have been developed about their structure rejuvenation and the possibilities of transformation them to a partially nanocrystalline state under the action of ultrasound. To summarise these developments, the systematic discussion on features, parameters, and modes of ultrasonic treatment applied to ribbon and bulk amorphous alloys to improve their structure-sensitive properties are provided in this review. On this basis, the limitations of current study are discussed. The most promising applications of ultrasonic technologies for rapidly melt-quenched alloys in the near future include: their additive manufacturing, creation of hybrid composites by ultrasonic welding, ultrasonic forming for manufacturing products of complex shapes and geometries, complex multi-stage processing to obtain a unique combination of properties (e.g., melt quenching → laser irradiation → ultrasonic stimulation). This review enhances the existing knowledge on ultrasonic control of the properties and structure of amorphous alloys and facilitates a fast references on this topic for researchers.



Interrelation between the microstructure and impact toughness of the interface of welded joints of 32HGMA and 40HN2MA steels produced by rotary friction welding
Abstract
This paper covers the assessment of the influence of the morphological features of the microstructure of medium-carbon alloyed steels, formed at different forces in the process of rotary friction welding (RFW), on the impact toughness of their interface. The paper presents the results of an experimental study of a joint produced by welding tubular billets of 32HGMA and 40HN2MA steels with an outer diameter of 73 mm and a wall thickness of 9 mm with a change in force at the stage of friction (heating) of the billets. The studies of the microstructure, microhardness and impact toughness on samples with a V-notch of welded joints were carried out in the initial state after welding and after tempering at a temperature of 550 °C. Macro- and microfractographic analysis of the destroyed samples was carried out. The study shows that the friction force affects the kinetics of phase transformations, phase composition and microstructure homogeneity in the steel junction zone. With a decrease in this parameter of rotational friction welding, the microstructure heterogeneity associated with the occurrence of upper bainite areas with uneven precipitation of large carbide particles increases, which has a negative effect on the viscosity of the steel interface both in the initial state and after tempering; the fracture mechanism is quasi-cleavage. At higher values of the friction force, the density of high-angle boundaries and the dispersion of the bainite microstructure increase, which ensures higher viscosity and energy capacity of destruction with the formation of a pitted microrelief. The obtained results open up space for regulating the visco-plastic properties of welded joints even at the welding stage without subsequent recrystallisation of the weld zone.



The influence of cavitational synthesis nanodiamonds on the tribological properties of a water-oil-based cooling lubricant
Abstract
This paper deals with the study of the influence of nanosized diamonds produced by the cavitational synthesis method on the tribological properties of a commercial water-oil-based cooling lubricant. The study is aimed at assessing the prospects for application of this type of nanodiamonds as an antifriction and antiwear additive. Tribological tests were carried out using the “indenter on a disk” friction scheme at a constant load and sliding speed. High-speed P18 steel for the indenter and 30HGSA steel for the rotating counterbody (disk) were used as friction couple materials. The studies were carried out for the base lubricant and two variants of its composition modifications using colloidal dispersion (distilled water with dispersed nanodiamonds) with a final additive concentration of 0.5 and 2.5 %. It was experimentally found that both variants of modification of the base water-oil emulsion resulted in increase of the bearing capacity of lubricating layers, decreasing the total linear wear of friction couple elements by 1.8–2.4 times. The presence of nanodiamonds in the composition enhanced as well the shielding effect of the cutting coolant. A decrease in visible damage to friction surfaces was recorded using optical microscopy. Analysis of profile diagrams of worn areas in the transverse direction showed a decrease in the size of a groove on the counterbody against the background of a decrease in roughness from Ra=0.49 μm in the basic variant to Ra=0.29–0.34 μm. Evaluation of the loss in counterbody weight for nanodiamond concentrations of 0.5 and 2.5 % showed a decrease in their value by 1.3 and 1.9 times, respectively; for the indenter, the decrease in this parameter was 1.2 and 1.5 times. Thus, the use of cavitational synthesis nanodiamonds as an additive may become a promising direction for increasing the antiwear properties of water-oil-based cooling lubricants.



The influence of hardening heat treatment modes on the crack propagation resistance of 5H2SMF die steel
Abstract
In the literature, there are virtually no data on the effect of quenching with holding in the pearlite and bainitic regions and subsequent low and high tempering of different durations on the crack propagation resistance of die steels, and the available data are contradictory. Meanwhile, a “softer” quenching with holding in the intermediate regions reduces significantly the risk of quenching cracks and deformation of dies and die tooling. In this work, samples of 5H2SMF die steel with a sharp notch and artificially induced cracks were subjected to heat treatment, including standard quenching at 910 °C in oil and quenching from 910 °C with steps at 650 °C and 340 °C with different types of tempering (200, 560, 600, and 640 °C) and different durations of time – 1, 3, 5, 7, and 14 h (for 200 °C) in order to increase the crack propagation resistance. The conducted studies allowed identifying that the data on crack propagation resistance after step quenching with holding in the pearlite transformation region and subsequent high tempering at 560, 600 and 640 °C are comparable with standard quenching in oil and high tempering at the same temperatures. The hardness after step quenching in the bainitic transformation region (340 °C) is significantly lower in all cases under different tempering conditions; therefore, it is not possible to compare crack propagation resistance with standard quenching. The optimal holding time (3 and 5 h) from the point of view of increasing crack propagation resistance after standard quenching from 910 °C in oil and low tempering at 200 °C was found.


