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Despite their complex composition, high-entropy alloys (HEAs) have a simple structure and have been extensively researched for their ability to achieve unique properties through thermo-mechanical processing (TMP). This review studies the effects of different rolling regimes and post-annealing on single and multiphase HEAs, analyzing how TMP leads to microstructural changes and improved mechanical properties. The rolling changes the shape and utilizes different mechanisms determined by the rolling temperature to strengthen the raw materials, thus affecting the HEAs' properties. The microstructural evolution of HEAs during annealing is affected by various parameters such as annealing time, annealing temperature, and heating rate, which impact the strength–ductility combination of HEAs. According to the literature, cryogenic rolling (cryo-rolling), as opposed to cold rolling, provides greater strengthening. This is due to the faster microstructural evolution kinetics in cryo-rolling. Thus, cryo-rolling enhances the strengthening by activating deformation twinning at earlier stages through the intersection of twins and more shear banding, which is preferred to microbands for HEAs with low stacking fault energy (SFE). Rolling at high temperatures is the most suitable approach for HEAs with low workability. Warm and hot rolling enable microstructure evolution through deformation mechanisms, including grain growth, recovery, recrystallization, and phase transformation based on the process temperature. The ratio of recovery to recrystallization depends on temperature and SFE, with recovery dominating in alloys with high SFE and at lower rolling temperatures, while recrystallization is more prevalent for alloys with low SFE and at higher temperatures, leading to specific ductility–strength synergy. [ABSTRACT FROM AUTHOR]

Materials with medical applications must show different properties and requirements, such as mimicking bones' structures and supporting bone tissue formation (osteogenesis) for implants. Magnesium (Mg) alloys as biodegradable materials have recently become outstanding biomaterials because of their desirable properties like being soluble within the body, having low density, exhibiting near-to-natural-bone Young module, and having after-corrosion-based products, which are not only biologically degradable but also non-toxic. In addition to the mentioned properties, the ability to stimulate new bone growth and more outstanding biocompatibility of Mg alloys than other ceramic-based, polymeric, and metallic biomaterials make Mg alloys one of the most favorable biomaterials for the next generation of orthopedic appliances and bioresorbable scaffolds. However, the rapid corrosion rate of Mg results in adverse outcomes such as hydrogen gas release (hydrogen built-up), mechanical integrity loss of the implant before the complete healing of the tissue (premature mechanical integrity disintegration), and weaker mechanical properties, which can limit their more comprehensive applications and restrict their ability in clinical bone restoration has become a challenge needing urgent action. The properties of Mg and its alloys, making them biomaterials and their applications, are introduced thoroughly in this study. At the same time, the most notable drawback of Mg, which is its rapid degradation rate, as well as Mg corrosion classification, its modeling approaches, and in vivo/in vitro testing methods, are fully described. Moreover, the relevant techniques to improve and boost its corrosion resistance, such as purification, adding alloying elements, surface coating, and Mg-based composites, are entirely presented. [ABSTRACT FROM AUTHOR]

This study investigates the influence of different annealing temperatures on the microstructure and growth of the intermetallic phase in an Al/Cu functionally graded metal matrix composite (FGMMC (produced by the accumulative roll bonding (ARB)-cold roll bonding (CRB) process. SEM images show the evolving distribution of Cu content in the composite, with the finest and thinnest Cu layer observed in the Al/20Cu region. The annealing at 400°C and 450°C for 2, 4, and 6 hours results in the formation of intermetallic layers (Al 2 Cu, Al 4 Cu 9 , and AlCu) with a clear progression from the Al side to the Cu side, as confirmed by SEM-EDS and TEM analysis. Increasing the annealing conditions increases the thickness of the intermetallic layers. In addition, the intermetallic layers are thicker in the FGMMC sample than in the ARB sample under the same conditions due to the additional strain during the process. The findings demonstrate that a diffusion-controlled mechanism governs the growth of the Al 2 Cu, Al 4 Cu 9 , and AlCu layers. The tensile test results indicate that as the Cu content increases from 20 wt% to 80 wt%, the ultimate tensile strength of the layers increases from 288.24 MPa to 373.66 MPa, while the elongation decreases from 8.2 % to 5.3 %. After annealing, however, these values decreased due to the restoration phenomenon and intermetallic formation. The fracture surface predominantly exhibits a brittle mode, especially with increasing Cu content and annealing conditions. • The Al/Cu FGMMC was fabricated by a new procedure consisting of ARB and CRB processes. • The copper layers were well distributed across the microstructure due to applying high strains. • With an increase in Cu content, the tensile strength increased and elongation decreased. • The formation sequence of the IMC layers was Al 2 Cu, Al 4 Cu 9 , and AlCu. The growth of IMCs is mainly controlled by diffusion. [ABSTRACT FROM AUTHOR]

For more than a decade many researchers have been developing new ways to produce laminated composites. In this paper, aluminum/titanium/steel multi-laminated composites were fabricated by the cross accumulative roll bonding (CARB) process, and effects of different rolling passes on microstructure, and mechanical properties were investigated. As the number of rolling passes increased, in spite of having no voids and cracks, more instabilities were observed on titanium and steel layers. With regard to mechanical properties, by increasing the rolling passes, the values of ultimate and yield strength, as well as elongation fell, because of the non-uniform distribution of hard layers within the aluminum matrix. Based on scanning electron microscopy (SEM) images, both ductile and cleavage modes of fracture were observed on fracture surfaces. Furthermore, with an increase in the number of rolling passes, the values of fracture toughness pertaining to the crack initiation declined on account of the increased probability of delamination. Plus, the trend of the R-curves was mainly downward due to the growing number of interfaces within the matrix by increasing the number of passes; nonetheless, the upward trend of these curves may be attributed to the ductile Al matrix in which the path of cracks can be bridged. Also, based on the results of wear tests, different wear mechanisms such as adhesion, abrasion, and delamination were observed, and with an increase in the number of rolling passes, the amount of weight loss showed a decline which was due to the rise of hardness concerning the strain-hardened layers. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article titled "A review on the effect of various rolling regimes (cryo, cold, warm, hot) and post-annealing on high-entropy alloys: microstructure evolution, deformation mechanisms, and mechanical properties." The correction states that the original article incorrectly assigned the author Mahdi DerakhshaniMolayousefi to Shiraz University of Technology, when it should have been Department of Materials Science and Engineering, Sahand University of Technology, Tabriz, Iran. The correction notice apologizes for the mistake and the publisher, Springer Nature, remains neutral regarding jurisdictional claims and institutional affiliations. The correction notice is authored by Moslem Tayyebi and Mahdi DerakhshaniMolayousefi. [Extracted from the article]

In this article, fracture behavior of multi-layered composite processed via accumulative roll bonding (ARB) method has been investigated. At first, Al1050/Cu/MgAZ31B multi-layered composite has been prepared by ARB through seven passes. The microstructure and mechanical properties have been evaluated using uniaxial tensile test, microhardness test and optical microscope, respectively. Then, the plane stress fracture toughness of Al1050/Cu/MgAZ31B have been studied via R-curves. Also, tensile fracture surfaces have been demonstrated by scanning electron microscope (SEM). The results of microstructure investigations have indicated that plastic instability occurred for both pure Cu and Mg AZ31B reinforcing at the primary sandwich and uniform distribution has been processed. By increasing the applied strain, the values of microhardness for the three layers Al1050, pure Cu, and Mg AZ31B as well as ultimate tensile strength (UTS) have been significantly increased, continually, and UTS has reached to the maximum value of 355.5 MPa. SEM images of the tensile rupture surfaces in the different ARB passes have demonstrated that with increasing the applied strain, the fracture mode converted to shear ductile at the last ARB pass. Results of fracture test have shown that by increasing the applied strain, the value of fracture toughness have been raised, continually and at the third pass reached to the maximum value of 40.4 MPam 1/2 . Also, the trends of fracture toughness for Al1050/Cu/MgAZ31B were in great matching with the conclusions of the fracture behavior investigation of Al1050 produced by ARB. [ABSTRACT FROM AUTHOR]

In the present study, a novel method for manufacturing functionally graded metal matrix composites (FGMMC) is introduced. This method is a cutting-edge combined plastic deformation process of accumulative roll bonding (ARB) and cold roll bonding (CRB) and was used to fabricate Al/Cu functionally graded composites. Several laminated composites with different content of Cu were first fabricated by the ARB process, then they were bonded by the CRB process as the volume fraction of Cu varies from the Al side to the Cu side. With an increase in Cu content, the hardness of layers rose. Furthermore, the SEM images showed the continuous changes of Cu content from the Al side to the Cu side of the composites. In addition, based on the results of the tensile test, since Cu layers act as reinforcements in the Al matrix, the strengths gradually grew with the progressive increase in the volume fractions of Cu. • Employing a new procedure consisting of ARB and CRB for producing Al/Cu FGMMC. • Good interface bond without voids and cracks was achieved. • Hardness values of laminated composites and their constituent rose with an increase in Cu content. • The tensile and yield strengths of the composite increased, from Al side to Cu side, by increasing the volume fraction of Cu. • The size and the number of voids on fracture surfaces decreased as the content of Cu grew. [ABSTRACT FROM AUTHOR]

Highlights: [•] Levonorgestrel (LeV) and megestrol acetate (MA) are progestogen compounds. [•] The solubilities were measured in supercritical carbon dioxide using a static method. [•] The measured solubilities of the drugs were correlated using semi-empirical models. [•] The M–T model is more suitable to describe the solubility of LeV and MA in SC-CO2. [•] The heat of drug-CO2 solvation and that of drug vaporization was approximated. [ABSTRACT FROM AUTHOR]

The last decades have seen a huge growth in the investigation of intermetallic compounds at the interfaces of laminated composites due to their useful features. In this research, effects of the formation of intermetallic compounds on tensile properties and wear resistance of Ni/Ti composites produced by cross-accumulative roll bonding (CARB) process have been examined at different annealing times and temperatures. Scanning electron microscopy (SEM) images demonstrated that the layers were well bonded together, but Ni layers experienced instabilities in light of plastic deformation. The EBSD results showed lamellar structure and crystallographic texture on Ti and Ni layers during plastic deformation. According to X-ray diffractometer (XRD) and energy-dispersive spectrometer (EDS) analyses, NiTi2 and NiTi were present in all annealed samples. The thickness of intermetallic compounds grew with an increase in annealing temperature and time. However, this growth led to a decrease in tensile strength while the values of elongation fluctuated. Based on the results of the wear test, the composite became more resistant to wear when the thickness of intermetallic layers increased. The surfaces of these layers with less roughness and lower coefficients of friction facilitated the movement of steel pin on samples during the wear test. Furthermore, wear mechanisms of adhesion, abrasion, and delamination were observed, and they were more noticeable at higher loads and lower annealing temperatures and times. [ABSTRACT FROM AUTHOR]

• According to the results of XRD and EDS, four intermetallic layers with the chemical composition of Cu9Al4-Cu4Al3-CuAl-Al2Cu were observed. • In each ARB passes, as the annealing temperature and time increased further, the strength was enhanced with the increasing thickness of the intermetallic compounds. • The maximum amount of tensile strength (345 MPa) was obtained in the third pass at 400 °C for 90 min. • In the third and fourth passes, the macroscopic path of fracture is observed with an angle of 35–45° to the direction of tension, which is due to the formation of shear deformation zones. • Fracture surfaces of the aluminum and copper layers were of a ductile type and knife-edge type without dimples and holes, respectively. This research aims to discuss the effect of annealing time and temperature on the interfacial and mechanical properties in Al5052/Cu multilayer composites processed by accumulative roll bonding (ARB). According to the results of XRD and EDS, four intermetallic layers with the chemical composition of Cu 9 Al 4 -Cu 4 Al 3 -CuAl-Al 2 Cu were observed at the interface of processed composite with three ARB passes after annealing at 400 °C for 90 min. The results of tensile properties in each specific ARB pass showed that at lower annealing temperatures and times, the recrystallization or recovery was dominant in mechanical properties, and the strength decreased, while at higher annealing temperature and time strength increased due to the thickening of intermetallic compounds. The maximum value of tensile strength (345 MPa) was obtained in the third pass at 400 °C for 90 min. Results of OM analysis on fracture surface by optic microscope of the composites annealed at 350 °C for 60 min demonstrated that from zero to the second pass the fracture path in the macroscopic state was perpendicular to the direction of stress. However, in the third and fourth passes, the macroscopic path of fracture is observed with an angle of 35–45° to the direction of tension, which is due to the formation of shear deformation zones. Also, SEM analysis of the third pass sample annealed at 400 °C for 60 min indicated that the fracture surface of the aluminum layer was ductile type but the copper layer was a knife-edge without dimples and holes. [ABSTRACT FROM AUTHOR]

This paper deals with the effects of three low-carbon steel filler metals consisting of ferritic and austenitic phases on the weld joints of the tungsten inert gas (TIG) welding of Hardox 500 steel. The correlation between the microstructure and mechanical properties of the weld joints was investigated. For this purpose, macro and microstructure were examined, and then microhardness, tensile, impact, and fracture toughness tests were carried out to analyze the mechanical properties of joints. The results of optical microscopy (OM) images showed that the weld zones (WZ) of all three welds were composed of different ferritic morphologies, including allotriomorphic ferrite, Widmanstätten ferrite, and acicular ferrite, whereas the morphology of the heat-affected zone (HAZ) showed the various microstructures containing mostly ferrite and pearlite phases. Further, based on mechanical tests, the second filler with ferritic microstructure represented better elongation, yield strength, ultimate tensile strength, impact toughness, and fracture toughness due to having a higher amount of acicular ferrite phase compared to the weld joints concerning the other fillers consisting of austenitic and ferritic-austenitic. However, scanning electron microscopy (SEM) images on the fracture surfaces of the tensile test showed a ductile-type fracture with a large number of deep and shallow voids while on the fracture surfaces resulting from the Charpy impact tests and both ductile and cleavage modes of fracture took place, indicating the initiation and propagation of cracks, respectively. The presence of acicular ferrite as a soft phase that impedes the dislocation pile-up brings about the ductile mode of fracture while inclusions may cause stress concentration, thus producing cleavage surfaces. [ABSTRACT FROM AUTHOR]

Highlights: [•] Desoxycorticosterone acetate (DA) and clobetasole propionate (CP) are natural hormones. [•] Solubilities of DA and CP were measured in supercritical carbon dioxide (SC-CO2). [•] The mole fraction solubilities of DA and CP in SC-CO2 ranged from 10−7 to 13.9×10−5. [•] Solubility data were correlated using four semi-empirical density-based models. [•] The heat of drug–CO2 solvation and that of drug vaporization was approximated. [ABSTRACT FROM AUTHOR]

Novel ultrasonically enhanced supramolecular solvent microextraction (USESSM) then high-performance liquid chromatography with ultraviolet detection have been used for extraction and determination of phthalates in water and cosmetics. Coacervates consisting of decanoic acid-based nano-structured aggregates, specifically reverse micelles, have been used the first time as solvents for ultrasound-assisted emulsification microextraction (USAEME). Sonication accelerated mass transfer of the target analytes into the nano-structured solvent from the aqueous sample, thus reducing extraction time. Several conditions affecting extraction efficiency, for example the concentrations of major components of the supramolecular solvent (tetrahydrofuran and decanoic acid), sample solution pH, salt addition, and ultrasonication time, were investigated and optimized. Under the optimum conditions, preconcentration of the analytes ranged from 176 to 412-fold and the linear range was 0.5-100 μg L, with correlation coefficients ( R) ≥ 0.9984. The detection sensitivity of the method was excellent, with limits of detection (LOD, S/ N = 3) in the range 0.10-0.70 μg L and precision in the range 4.1-11.7 % (RSD, n = 5). This method was successfully used for analysis of phthalates in water and cosmetics, with good recovery of spiked phthalates (91.0-108.5 %). [ABSTRACT FROM AUTHOR]

• Producing multi-layered composite of Cu/Zn/Al by cross accumulative roll bonding. • Adhesion, abrasion, and delamination wear mechanisms occurred in CARBed samples. • The maximum fracture toughness value was obtained for the third cycle to be about 31 MPa.m1/2. • After the third cycle, the fracture toughness of the composite samples was gradually decreased by increasing the CARB cycles. • By introducing the Al and Zn layers to the surface of the composite samples during CARB, the corrosion resistance decreased. In this research, the structure, tensile, wear, fracture toughness, and corrosion characteristics of Cu/Zn/Al multilayered composites fabricated by cross accumulative roll bonding (CARB) were determined. X-ray diffraction and scanning electron microscopy were used for structural analyses. Results showed that the crystallite size of the Cu matrix is reduced to about 50 nm at the ninth cycle of CARB, while the plastic instability and shear bands appeared in the layers after the third cycle. The tensile strength of the composites increased up to the third CARB cycle and then decreased to the ninth CARB cycle gradually. Typically, the maximum strength of about 330 MPa and elongation of almost 31.5% were obtained at the third and first cycles, respectively. A similar trend was found for the fracture toughness of the samples, so that the maximum fracture toughness of about 31 MPa.m1/2 was obtained at the third cycle. It was also shown that the wear mechanism of the composite samples changes by increasing the cycles, a compromise of abrasion and delamination wear. The accommodation of Al and Zn layers toward the surface of the composites by increasing the CARB cycles was also recognized to be responsible for the decrease of the corrosion resistance determined by polarization experiments. [ABSTRACT FROM AUTHOR]