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The current study aimed to investigate the effect of shot peening on steel with 11% Cr in order to induce compressive residual stress. Shot peening was carried out for durations of 5, 10, 15, and 20 minutes to vary the level of compressive residual stress. x-ray diffraction (XRD) equations were employed to evaluate the crystallite size, lattice strain, dislocation density, and generated residual stress. The findings revealed that an increase in shot-peening time resulted in significant plastic deformation on the surface of the samples. Consequently, there was a reduction in crystallite size down to 10.60 nm. The decrease in crystallite size corresponded with observed severe lattice strain leading to a displacement density reaching up to 0.00889. Moreover, upon transforming dislocations into main grains during this process, there was an elevation in compressive residual stress levels up to approximately 694.5 MPa. Initially during shot peening at early stages, any generated residual stress was negligible but eventually increased threefold after reaching 10 minutes. [ABSTRACT FROM AUTHOR]

The present paper deals with twinning-induced plasticity (TWIP) steels with the microstructure refined by severe plastic deformation via equal channel angular pressing and explores the mechanical behavior of steel with qualitatively different microstructures formed in the temperature range 400–900°C. Mechanical characteristics of the steel in different structural states are studied in static tensile tests, biaxial and dynamic tests. Structural changes in the material during severe deformation at different temperatures are discussed, and their effect on the mechanical parameters of TWIP steel is considered. High temperatures of equal channel angular pressing allow for more homogeneous recrystallized structures, which ensure the best combination of the yield stress, formability, plasticity, and crack resistance. These findings can be important in developing high-performance steels for the automotive and hydrogen industries. [ABSTRACT FROM AUTHOR]

The evolution of the crystallographic texture after severe plastic deformation (SPD) of the aluminum alloy AA7075, commonly used in the aeronautical and automotive industries, depends on the parameters of the applied deformation process. In this paper, a combination between experimental ECAP processing and numerical simulation using the visco-plastic self-consistent methodology (VPSC) was carried out. The limitations in the homogeneity of the mechanical properties and texture of the parts processed via ECAP can be improved by an adequate choice of the processing route. According to the literature, the most effective route to increase the properties of this material is the Bc route. However, due to the two-fold symmetry along the extrusion axis, the Bc route cannot be used in the components under study. Because of this, it was decided to study C and modified C routes. The simulation results showed the characteristic fibers of the ECAP process measured through X-ray diffraction. The texture analysis shows that the most effective route to obtain a more homogenous shear deformation and therefore reduce the grain size is the Bc route, followed by the modified C route and finally the C route. [ABSTRACT FROM AUTHOR]

The long-term corrosion resistance of commercially pure aluminum (AA1050) processed by equal channel angular pressing (ECAP) was evaluated in a saline environment. The study compared the microstructure and corrosion behavior of ECAP-processed samples in route A with 1X, 4X, and 8X passes to an annealed sample using a 3.5% NaCl solution. Characterization techniques, including optical microscopy (OM), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), and electrochemical impedance spectroscopy (EIS), were employed. Results indicate that ECAP processing enhances the passive corrosion resistance compared to the undeformed sample. However, the improvement in corrosion resistance did not consistently increase with the number of ECAP passes. Factors such as the distribution of high- and low-angle grain boundaries, dislocation density, and fragmentation and redistribution of coarse dispersoid particles play a significant role in the corrosion behavior post-ECAP. Additionally, findings suggest that long-term immersion tests are required to obtain a more reliable electrochemical response. [ABSTRACT FROM AUTHOR]

The aim of this study was the synthesis of intermetallic crystal dispersion in an ultra-fine-grained (UFG) aluminum matrix by the equal-channel angular pressing (ECAP) process, which provides severe plastic deformation (SPD) of aluminum-5 and 10% wt. nickel powders. The ECAP process of up to 20 passes was carried out at 200 °C. Intermetallic crystal particles in the UFG Al matrix were obtained in sintered samples at 500 °C for 1 and 5 h, interrupting the ECAP process. The scanning electron microscope (SEM) images were received for the microstructural evaluations. According to the SEM images, it was understood according to the quantitative observation and energy dispersive spectroscopy (EDS) analysis results that the Ni powders added to Al mostly remained in the block state in the matrix structure after the ECAP processes but started to dissolve in the matrix by increasing the ECAP pass number and sintering temperature. DSC and XRD analyses were carried out to investigate intermetallic crystal evaluation in the material. According to DSC analyses, the melting degrees of the alloys increase with the amount of Ni added. Melting enthalpies and melting degrees showed small changes in the number of ECAP passes. Also, electron backscatter diffraction (EBSD) images were obtained for the samples' grain size and grain boundary angle measurements. It has been understood that the number of passes and the process temperature are effective parameters for the solid-state synthesis of Al3Ni intermetallic crystals in UFG by the ECAP process. [ABSTRACT FROM AUTHOR]

The mechanical behavior and the microstructural evolution of a pearlitic SAE 1080 steel were analyzed along 12 Multi-Directional Forging (MDF) cycles at room temperature and strain amplitude Δε ≈ 0.30 (MDF0.30). The resulting cumulative strain flow curve is typical of metals undergoing extensive dynamic recovery, displaying appreciable work hardening up to a strain εt ≈ 0.9, followed by a very low work hardening, where flow stress rises from ≈1400 MPa to ≈1510 MPa. Similarly, the microhardness raises up to a total cumulative strain εt ≈ 1.8 and seems to stabilize for further straining, reaching ∼3626 MPa after εt ≈ 10.8. Conversely, yield strength initially rises and then falls remarkably after εt > 5.4. This behavior is related with directional cross effects that favor dynamic recovery as the total applied strain increases. These results differ remarkably from those connected to a monotonic deformation process such as axisymmetric drawing. In addition, directional cross effects decrease the material yield stress as the total applied strain increases. Microstructural results revealed that MDF0.30 leads to increasing shearing, bending and fragmentation of the cementite lamellae into particles

The paper covers the production, analysis of the microstructure, crystallographic texture and deformation mechanisms of the ultrafine-grained (UFG) Zn–1%Mg–1%Fe zinc alloy demonstrating unique physical and mechanical properties compared to its coarse-grained analogues. The zinc alloy with improved mechanical properties was developed in two stages. At the first stage, based on the analysis of literature data, an alloy with the following chemical composition was cast: Zn–1%Mg–1%Fe. Then, the alloy was subjected to high-pressure torsion (HPT) to improve mechanical properties, due to grain structure refinement, and implementation of dynamic strain aging. The conducted mechanical tensile tests of the samples and assessment of the alloy hardness, showed that HPT treatment leads to an increase in its tensile strength to 415 MPa, an increase in hardness to 144 HV, and an increase in ductility to 82 %. The obtained mechanical characteristics demonstrate the suitability of using the developed alloy in medicine, as some implants (stents) requiring high applied loads. To explain the reasons for the improvement of the mechanical properties of this alloy, the authors carried out comprehensive tests using microscopy and X-ray diffraction analysis. The microstructure analysis showed that during the formation of the ultrafine-grained structure, a phase transition is implemented according to the following scheme: Zneutectic + Mg2Zn11eutectic + FeZn13 → Znphase + Mg2Zn11phase + MgZn2particles + Znparticles. It was found that as a result of high pressure torsion in the main phases (Zn, Mg2Zn11), the grain structure is refined, the density of introduced defects increases, and a developed crystallographic texture consisting of basic, pyramidal, prismatic, and twin texture components is formed. The study showed that the stability of pyramidal, prismatic and twin texture components at the initial stages of high-pressure torsion, determines the level and anisotropy of the strength properties of this alloy. The relationship between the discovered structural features of the produced alloy and its unique mechanical properties is discussed.

The metallic materials subjected to machining‐induced severe plastic deformation can experience alterations of microstructures and mechanical properties, affecting the functional performances of the components. This study concentrates on the microstructure evolution and mechanical properties analysis of Ni‐based superalloy Inconel 690 under severe plastic deformation induced by milling process. The obtained results show that the microstructures of the machined surface and subsurface exhibit the characteristic of gradient distribution. Plastic behaviors involving dislocation multiplication, grain deformation and refinement, increment of local misorientation and average intragranular misorientation, and transition from high‐angle grain boundaries to low‐angle grain boundaries occur in the superficial layer of the machined workpiece. Both the intensity and the affected depth of plastic deformation for the superficial layer are strengthened following the cutting speed and feed increase, which is attributed to higher cutting forces. No white layer and phase transformation is found under all cutting conditions. In addition, the nanohardness of the superficial layer shows the reduction tendency of hardening effect from the surface to the bulk of the machined workpiece material. With the increase in cutting speed and feed, the affected zones of residual stresses and work hardening below the machined surface become wider. [ABSTRACT FROM AUTHOR]

Traditionally, structural wire is characterized by a homogeneous microstructure, where the average grain size in different parts of the wire is uniform. According to the classical Hall–Petch relationship, a homogeneous polycrystalline metal can be strengthened by decreasing the average grain size since an increase in the volume fraction of grain boundaries will further impede the motion of dislocations. However, a decrease in the grain size inevitably leads to a decrease in the ductility and deformability of the material due to limited dislocation mobility. Putting a gradient microstructure into the wire has promising potential for overcoming the compromise between strength and ductility. This is proposed a new combined technology in this paper in order to obtain a gradient microstructure. This technology consists of deforming the wire in a rotating equal-channel step die and subsequent traditional drawing. Deformation of copper wire with a diameter of 6.5 mm to a diameter of 5.0 mm was carried out in three passes at room temperature. As a result of such processing, a gradient microstructure with a surface nanostructured layer (grain size ~400 nm) with a gradual increase in grain size towards the center of the wire was obtained. As a result, the microhardness in the surface zone was 1150 MPa, 770 Mpa in the neutral zone, and 685 MPa in the central zone of the wire. Such a symmetrical spread of microhardness, observed over the entire cross-section of the rod, is a direct confirmation of the presence of a gradient microstructure in deformed materials. The strength characteristics of the wire were doubled: the tensile strength increased from 335 MPa to 675 MPa, and the yield strength from 230 MPa to 445 MPa. At the same time, the relative elongation decreased from 20% to 16%, and the relative contraction from 28% to 23%. Despite the fact that the ductility of copper is decreased after cyclic deformation, its values remain at a fairly high level. The validity of all results is confirmed by numerous experiments using a complex of traditional and modern research methods, which include optical, scanning, and transmission microscopy; determination of mechanical properties under tension; and measurement of hardness and electrical resistance. These methods allow reliable interpretation of the fine microstructure of the wire and provide information on its strength, plastic, and electrical properties. [ABSTRACT FROM AUTHOR]

In this paper, ultrasonic surface rolling processing (USRP) is used to process GCr15 (AISI-52100), and a three-dimensional ultrasonic surface rolling processing simulation model is established by finite element method to analyze the influence mechanism of static pressure on residual stress. The design L9 orthogonal test studied the importance of USRP parameters on the surface roughness of GCr15 bearing steel. The influence mechanism of process parameters (feed, static pressure, and rotational speed) on the surface microhardness, microstructure, and wear resistance of GCr15 was also studied. The results show that when the process parameters 1400 N, 0.08, and 100 r/min (specimen A7) were selected for machining, the plastic deformation of the specimen was the most intense and the surface grains were refined, forming a grain refinement layer with a thickness of about 10 μm. The surface defects of the specimen are reduced, and the surface roughness is as low as 0.076 μm. The surface microhardness can reach up to 806.2 HV0.5. And the surface roughness, surface hardness, and residual stress increased by 12.56, 65.91, and 138.89%, respectively. After the USRP treatment, the coefficient of friction of the material is reduced, and the amount of wear is reduced by 30%. The wear mechanism also gradually changes from adhesive wear to abrasive wear. [ABSTRACT FROM AUTHOR]

The changes in structure and strength of the 1965 aluminum alloy ingot caused by the isothermal multi-step forging and cryorolling are analyzed. It is shown that forging, in addition to refining grains and excess phases, increases the homogeneity of the spatial distribution of transition metal (TM) aluminides and improves the alloy strength and ductility in the T6 condition. The development of a nanocellular structure with strings of excess phases and uniformly distributed TM aluminides due to cryorolling leads to a unique strength-ductility balance in the naturally aged alloy. [ABSTRACT FROM AUTHOR]

The article presents investigations of microstructure and low‐temperature mechanical properties of nanostructured alloys CoCrFeMnNiVx (x = 0.15–0.75), processed by high‐pressure torsion (HPT) at temperatures of 300 and 77 K. While at x ≥ 0.5 the values of microhardness (Hv) and compression yield stress (σ0.2) in samples after HPT at 77 K are larger than those in samples after HPT at 300 K, for x ≤ 0.2 surprisingly the opposite effect is observed. As in case of the undeformed CoCrFeMnNiVx alloys, the behavior for vanadium concentrations x ≥ 0.5 can be related to the formation of tetragonal σ‐phase in addition to face‐centered cubic matrix, while the anomalous behavior for x ≤ 0.2 arises from the formation of HPT‐induced hexagonal martensitic phase. In the low‐temperature ranges, i.e., 20–300 K in case of HPT nanostructured CoCrFeMnNiV0.2, and 150–300 K in case of HPT nanostructured CoCrFeMnNiV0.5, dependences of σ0.2(T) show characteristics of thermally activated dislocation movement. For the first time in high‐entropy alloys, anomalous dependences of σ0.2(T) at temperatures 4.2–20 K for CoCrFeMnNiV0.2, and at 80–150 K for CoCrFeMnNiV0.5 are found, which indicate at the occurrence of nonthermal inertial dislocation movement. [ABSTRACT FROM AUTHOR]

The use of pressure to achieve superior properties in metals, especially for use in a range of weaponry, has a long history dating back to the artisans of ancient China and many parts of Asia. Nevertheless, scientific principles were not introduced until the classic experiments conducted by Nobel Laureate Professor Percy Bridgman at Harvard University almost 100 years ago and these experiments led directly to the development of metal processing through the procedure now known as high‐pressure torsion (HPT). This review provides a brief overview of the historical evolution of pressure as a convenient tool in metal‐working and then summarizes the major features associated with the processing of metals by HPT and, more recently, the torsional straining of stacked disks in HPT to produce a range of hybrid materials. Finally, there is a brief report on the development of the relatively new processing procedure of tube high‐pressure shearing (t‐HPS) which may be used for the fabrication of metal matrix composites. [ABSTRACT FROM AUTHOR]

The deformation of multiphase metallic alloys or metal matrix composites by forming processes such as rolling or drawing requires the co‐deformation of phases. Severe plastic deformation processes have extended possibilities with the ability to produce unique nanoscaled structures through the formation of strain‐induced super‐saturated solid solutions, the fragmentation of second‐phase particles, or ultimate co‐deformation down to the nanoscale. Based on various examples, the fundamental mechanisms of co‐deformation are addressed. Parameters that promote the extension of existing heterophase boundaries are discussed, and some possible atomic‐scale mechanisms involving dislocation activities based on geometrical and energetic considerations are proposed. Finally, the physical limits of co‐deformation are considered before suggesting research directions that might be followed to develop fundamental knowledge and applications in the field. [ABSTRACT FROM AUTHOR]

High pressure torsion (HPT) is presented as a new fabrication route to produce bulk Sm–Co magnets with a strongly refined microstructure down to the nanometer regime. The initial powders, based on the compositions SmCo5, Sm2Co7 and Sm2Co17, are compacted and subsequently deformed by HPT. The microstructural evolution in dependence on the applied deformation parameters is characterized by electron microscopy and the effect of HPT on the phase stability is monitored by synchrotron X‐ray diffraction. An increasing amount of applied strain leads to a stronger reduction in grain size while strain localization counteracts a homogeneous microstructural refinement. The positive effect of elevated deformation temperatures is demonstrated for Sm2Co17, which promotes homogeneous grain refinement, but causes strain‐induced phase transformations at the same time, strongly affecting the magnetic behavior. Superconducting quantum interference device magnetometry is used to characterize the magnetic properties after HPT deformation, which indicates the formation of a magnetic texture depending on the respective phase. [ABSTRACT FROM AUTHOR]

Astronomical impacts by small solar system bodies (meteoroids, asteroids, comets, and transitional objects) are considered a mechanism for delivering amino acids and their polymerization to proteins in early Earth conditions. High‐pressure torsion (HPT) is a new methodology to simulate such impacts and clarify the behavior of biomolecules. Herein, two amino acids, crystalline L‐serine and L‐glutamic acid that are detected in meteorites, are processed by HPT and examined by ex situ X‐ray diffraction, Raman spectroscopy, nuclear magnetic resonance, Fourier‐transform infrared spectroscopy, and in situ mechanical shear testing. No polymerization, chemical reactions, or phase transformations are detected after HPT, indicating that the stability and presence of these two amino acids in meteorites are quite reasonable. However, some microstructural and mechanical changes like crystal size reduction to the nanometer level, crystal defect formation, lattice expansion by vacancy formation, and shear strength enhancement to the steady state are found which are similar to the behaviors reported in metals and ceramics after HPT processing. [ABSTRACT FROM AUTHOR]

Reducing the saturation magnetostriction is an effective way to improve the performance of soft magnetic materials and reduce core losses in present and future applications. The magnetostrictive properties of binary Fe-based alloys are investigated for a broad variety of alloying elements. Although several studies on the influence of Cu-alloying on the magnetic properties of Fe are reported, few studies have focused on the effect on its magnetostrictive behavior. High pressure torsion deformation is a promising fabrication route to produce metastable, single-phase Fe-Cu alloys. In this study, the influence of Cu-content and the chosen deformation parameters on the microstructural and phase evolution in the Fe-Cu system is investigated by scanning electron microscopy and synchrotron X-ray diffraction. Magnetic properties and magnetostrictive behavior are measured as well. While a reduction in the saturation magnetostriction λs is present for all Cu-contents, two trends are noticeable. λs decreases linearly with decreasing Fe-content in Fe-Cu nanocomposites, which is accompanied by an increasing coercivity. In contrast, both the saturation magnetostriction as well as the coercivity strongly decrease in metastable, single-phase Fe-Cu alloys after HPT-deformation. [ABSTRACT FROM AUTHOR]

Metal screw extrusion (MSE) is a continuous, solid-state forming method utilizing an inherently high degree of deformation to consolidate fragmented input materials into a solid bulk by breaking their oxide skins. Severe plastic deformation with equivalent strain in the range of 10–20 can be achieved depending on set process parameters. Rigorous mixing can be employed to form sophisticated materials like bulk composites, nanocomposites, particle-reinforced metals, and fine-grained materials. Furthermore, the inherent solid-state processing is well suited for recovery of difficult-to-recycle materials. A range of non-ferrous materials has been manufactured by MSE and further characterized in terms of microstructural evolution and mechanical and functional properties. Furthermore, MSE has been studied in terms of flow, accumulated strain, and environmental impact. The following review aims to critically highlight the existing work performed on MSE, compare it to existing and emerging technologies as well as explore future development and possible applications. MSE has the potential to be utilized for numerous commercial applications. To realize industrial use of MSE, key aspects of the process and the influence of processing parameters on the resulting product must be understood. [ABSTRACT FROM AUTHOR]

In this study, the corrosion behavior and microstructural transformations of 1000 series aluminum and copper tubes after an explosive welding process were investigated. Welding was performed with a fixed stand-off distance and various explosion thicknesses. Explosive welding was carried out using a consistent stand-off distance of 2 mm while varying the thickness of the explosive material of 60 mm (sample 1) and 80 mm (sample 2). The explosion velocity employed during the process was measured at 2504 m/s. Optical and electron microscopy images revealed that the thickness of the melting layer at the interface increases proportionally with the thickness of the explosive charge. Specifically, as the explosive thickness increased from 60 to 80 mm, the thickness of the melting layer increased as well. Also, the resuls of the potentiodynamic polarization test indicated a decrease in the corrosion potential from –670 mV (sample 1) to –665 mV (sample 2) as the explosive material thicknesses increased. At the same time, the corrosion current density rose from 52.34 µA/cm2 (sample 1) to 78.32 μA/cm2 (sample 2). An analysis of the Nyquist diagram for explosive welding samples revealed that the curve radius of sample 2 exceeded that of sample 1, suggesting a higher corrosion resistance in sample 1 compared to that in sample 2. [ABSTRACT FROM AUTHOR]

The technology of manufacturing aluminum alloy workpieces using additive friction stir deposition (AFS‐D) has been thoroughly investigated. The ambiguous influence of deformation processing modes on the material density was found. Examination of the microstructure in the central zone of the specimens reveals the absence of microdefects typically associated with workpieces obtained through casting or powder metallurgy methods. It has been observed that the distribution of microhardness is significantly affected by the direction of specimen construction, with approximately a 20% difference in values between the periphery and the central part of the specimen. Specimens produced using the AFS‐D method exhibit a homogeneous microstructure characteristic of deformable aluminum alloys. Notably, a uniform distribution of intermetallides on the specimen surface has been identified. This outcome is likely a result of the alloy undergoing recrystallization during the severe plastic deformation process, leading to the formation of an ultradisperse structure. It is important to emphasize that the selection of technological parameters for AFS‐D should consider not only the magnitude of pressure and deformation but also the deformation speed. [ABSTRACT FROM AUTHOR]

Titanium Grade 2 strips or sheet metal, a commercial alloy used extensively in airframes, aircraft engines, marine applications, tubing and orthopedic implant/prosthetics, has been manufactured employing Large Strain Extrusion Machining (LSEM) process. LSEM is one of the severe plastic deformation processes (SPD), involving very large strains and shear forces, converting bulk material into very thin strips or sheets in a single pass. The strips or sheets produced by LSEM have improved bulk mechanical properties over the raw material owing to severe plastic deformation. The current work focusses on the influence of cutting speeds on the fabricated Titanium Grade 2 strips by LSEM on surface integrity in terms of surface microstructure, hardness, surface roughness, induced surface residual stresses and corresponding surface corrosion. The study showed that variation in cutting speed has significant bearing on surface characteristics of the strips produced employing LSEM. At comparative lower cutting speeds, surface quality and corrosion resistance of the produced strip is enhanced. [ABSTRACT FROM AUTHOR]

This study highlights the effect of high-pressure torsion (HPT), a severe plastic deformation technique, on the magnetic properties of equiatomic FeNi alloys prepared from mechanical alloying. The prime objective of this study is to increase the interdiffusion of FeNi and accelerate the formation of L10 ordering. HPT processing on FeNi alloy was carried out at room temperature under 6 GPa for 5, 10 and 20 turns. Subsequently, the samples were subjected to heat treatment in a vacuum at 593 K for 1000 h without any magnetic field. Further heat treatment of 4 h was also performed at 593 K in the presence of a 1.5 T magnetic field. It is observed that HPT processing first increases the lattice strain; however, further processing causes strain relaxation due to dynamic recrystallization. Initially, for 5 turns of HPT, the saturation magnetization decreases. However, after 10 and 20 turns of HPT, the saturation magnetization increases due to recrystallization and formation of L10 ordering. After 5 turns, the coercivity increases by ~175% due to lattice strain. With further processing, the coercivity decreases by ~50% due to recrystallization. Heat treatment on the HPT-processed samples shows increased coercivity and remanence due to the annihilation of defects and formation of short-range L10 ordering. [ABSTRACT FROM AUTHOR]

This article presents the results of research on a new combined process involving multi-cycle wire-drawing and subsequent cryogenic cooling after each deformation stage. For theoretical research, modeling in the Deform software was performed. The analysis of temperature fields and the martensitic component in all models showed that for both considered thicknesses, the most effective option is a low deformation velocity and the conduct of a process without heating. The least effective option is to use an increased thickness of the workpiece at an increased deformation velocity and the conduct of a process without of heating to ambient temperature, which acts as a local cooling of the axial zone of the workpiece with an increase in the workpiece thickness. An analysis of laboratory studies on this combined process revealed that in the absence of intermediate heating of a wire between deformation cycles, 100% martensite is formed in the structure. However, if intermediate heating to 20 °C between deformation cycles is carried out, a gradient distribution of martensite can be obtained. And, since the wire has a circular cross-section, in all cases, martensite is distributed symmetrically about the center of the workpiece. [ABSTRACT FROM AUTHOR]

In this study, we focused on the effects of various deformation amounts and subsequent heat treatment on σ-phase precipitation in CoCrFeMnNi high entropy alloy, known as Cantor alloy. Homogenized specimens with an initial FCC single-phase structure were deformed to various shear strains (1.1-25.8) using high-pressure torsion (HPT). This process resulted in a variety of deformation microstructures, with low to medium shear strains leading to the formation of twin-matrix lamellae intersected by shear bands, while high shear strains resulted in nanocrystalline structures. After deformation, the specimens were heat-treated at 700°C for up to 5 h, which led to recrystallization of the FCC matrix accompanied by precipitation of σ phase. The kinetics of recrystallization and precipitation and their interactions during the heat treatment were greatly different among the specimens with different degrees of pre-deformation. Notably, the precipitation of σ phase was accelerated in the specimens subjected to higher shear strains, particularly in those with nanocrystalline structures. The increased rate of precipitation was beneficial for grain refinement since the presence of numerous precipitates within the recrystallized microstructures inhibited their grain growth. Tensile testing of the heat-treated specimens displayed various combinations of strength and ductility, with specimens subjected to higher predeformation exhibiting enhanced strength due to finer recrystallized grain sizes and larger fractions of precipitates. Our findings offer valuable insights into fabrication processing of HEAs, aiming to optimize microstructure and mechanical properties for potential engineering applications. [ABSTRACT FROM AUTHOR]

The 18th International Conference on Aluminium Alloys (ICAA18) was held in Toyama, Japan from September 4 to 8, 2022, and the special issue entitled "Aluminium and Its Alloys for Zero Carbon Society" was published on Materials Transactions in February 2023 (Vol. 64, No. 2). The biennial conference covered a wide range of current trends in aluminium research; e.g. "modeling and simulation", "casting, solidification, recycling and refining", "additive manufacturing", "foams and composite materials", "mechanical properties and advanced processing", "thermomechanical processing, texture and recrystallization", "heat treatment, phase transformation and precipitation", "corrosion and surface treatments", "joining, emerging processes and multi material" and "advanced characterization". This article briefly reviews selected papers from the conference with significant experimental outcome and discussion on aluminium alloys. The author hopes that these papers are useful for all the researchers who develop next-generation technologies and materials concerning aluminium alloys. [ABSTRACT FROM AUTHOR]

An algorithmic approach for determining the relationship between the energy of grain boundaries and their location in the structure has been developed and proposed. A comparative analysis of the results of relative grain boundary energies measurements by the method of etch groove shape analysis for "manual" measurement and the developed algorithmic approach was carried out on the example of ultrafine-grained nickel obtained by severe plastic deformation. [ABSTRACT FROM AUTHOR]

A study of the phase transformation in technically pure titanium under different types of deformation has been performed: upset under high pressure and high hydrostatic-pressure torsion (HPT). A set of modern methods of the study included microindentation, X-ray diffraction, transmission electron microscopy, as well as EXAFS-spectroscopy in synchrotron radiation for detailed studying a local atomic structure of phases. The correlation between the phase transformation course and the deformation method has been found. It has been shown that in contrast to pressure without a shear component, the shear deformation under high pressure at room temperature contributes to the occurrence of a high-temperature β-phase with a local atomic order different from that in the initial phase. [ABSTRACT FROM AUTHOR]

The use of low-carbon unalloyed steel with minimal silicon content is widespread in structural steel and automotive applications due to its ease of manipulation. The mechanical properties of this steel can be significantly enhanced through severe plastic deformation (SPD) techniques. Our study focuses on the practical benefits of the dual rolling equal channel extrusion (DRECE) method, which strengthens the steel and has implications for material hardness and the thickness of subsequently applied hot-dip zinc galvanizing. Furthermore, the steel's corrosion potential and current are investigated as a function of material hardness and thickness. The findings show a 20% increase in hardness HV 30 after the first run through the forming machine, with an additional 10% increase after the second run. Subsequent galvanizing leads to a further 1–12% increase in HV 30 value. Notably, the DRECE hardening demonstrates no statistically significant effect on the corrosion potential and current; however, the impact of galvanizing is as anticipated. [ABSTRACT FROM AUTHOR]

The purpose of this work is a comparative analysis of the workpiece shape, and parameters of the stress-strain state during deformation on two radial-shear rolling mills with different roll configurations to determine the most suitable scheme for obtaining a screw reinforcement profile. During the FEM simulation of the radial-shear rolling process in the DEFORM program, a comparison of the workpiece shape change after rolling, equivalent strain, damage index, and Lode–Nadai index was carried out. Steel 10 (analogue of AISI 1010) was chosen as material workpiece. The analysis of the obtained data revealed that the most rational choice for the implementation of the reinforcement profile production process is the radial-shear rolling mill RSR 10-30. Subsequent modeling of the combined process of radial-shear rolling and twisting in a screw matrix showed that when using rolls of RSR 10-30 mill, the screw profile of the workpiece is formed successfully, whereas using rolls of the SVP-08 mill, the formation of a screw profile is impossible due to jamming due to an irregular cross-section shape. A laboratory experiment confirmed the possibility of forming a screw reinforcement profile at RSR 10-30 mill, and an assessment of the geometric parameters of the final workpiece showed full compliance with the dimensions of the profiles obtained during modeling and experiment. [ABSTRACT FROM AUTHOR]

Tubular Channel Angular Pressing (TCAP) is among the upcoming and highly interesting, severe plastic deformation methods (SPD). This technique is reported to be appropriate for the deformation of very large strains in cylindrical tubes. The tube is pressed by a top die in a space between a mandrel and a die containing three shear zones while maintaining the same tube thickness and diameters. To investigate the SPD process in tubular samples, a commercially available pure aluminium alloy (AA7075) was used to evaluate the influence of die geometry, coefficient of friction, pressing speed, die temperature and tube thickness. The average grain size of about 500 nm was attained from 25 μm by extensive grain refinement. The results of Finite Element (FE) indicated that an effective strain of 3 was achieved by correctly choosing the input parameters. The thickness and length of the tube processed by TCAP also exhibited excellent strain homogeneity. The TCAP process can impose large strains because of having three deformation zones. Depending on input parameters selection, this SPD method, therefore, has two major advantages; (i) excellent strain homogeneity and (ii) high effective strain. [ABSTRACT FROM AUTHOR]