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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]

The purpose of this paper is to examine the microstructural evolution and mechanical properties of Ni/Ti laminated composite produced by a cross-accumulative roll bonding (CARB) method. The SEM images showed that no void and delamination were observed which indicates that the layers were strongly bonded together. In addition to the thickness reduction and increased number of interfaces, plastic instabilities took place with an increase in CARB passes; the wavy-like interfaces appeared as a result of the necking and shear bands formation. However, due to the effect of uniform rolling pressure and rotation of rolling direction during the CARB process, all layers remained continuous in all CARB passes. The most marked observation coming from EBSD analyses was the formation of fine grains surrounded by a high fraction of high-angle grain boundaries (HAGBs). Based on the microtexture analyses on Ti and Ni layers, it was found that by increasing the rolling passes, a crystallographic texture formed in Ti layers gradually changes from the basic {0001}<112 ̅0 > system into the system dominated by {0001}<101 ̅0 > prismatic-like orientations. In the case of the crystallographic texture formed in Ni layers, there was a significant increase in the intensity of the Q{013}<231>; P{011}<122 > and Goss {011}<100>, indicating the formation of shear strain-assisted type of texture. Furthermore, with an increase in the CARB passes, the mechanical properties improved due to strong interfaces and grain refinement. The maximum values of the yield strength, tensile strength, and elongation reached 842 MPa, 936 MPa, and 7.1% respectively, in the final CARB pass. In addition, ductile fracture mainly occurred on fracture surfaces of Ti and Ni layers even though by increasing passes, cleavage facets appeared due to strain hardening. [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]

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]

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 the present study, an Al/Cu/Mg multi-layered composite was produced by accumulative roll bonding (ARB) through seven passes, and its microstructure and mechanical properties were evaluated. The microstructure investigations show that plastic instability occurred in both the copper and magnesium reinforcements in the primary sandwich. In addition, a composite with a perfectly uniform distribution of copper and magnesium reinforcing layers was produced during the last pass. By increasing the number of ARB cycles, the microhardness of the layers including aluminum, copper, and magnesium was significantly increased. The ultimate tensile strength of the sandwich was enhanced continually and reached a maximum value of 355.5 MPa. This strength value was about 3.2, 2, and 2.1 times higher than the initial strength values for the aluminum, copper, and magnesium sheets, respectively. Investigation of tensile fracture surfaces during the ARB process indicated that the fracture mechanism changed to shear ductile at the seventh pass. [ABSTRACT FROM AUTHOR]

In this study, a multilayer Al/Ni/Cu composite reinforced with SiC particles was produced using an accumulative roll bonding (ARB) process with different cycles. The microstructure and mechanical properties of this composite were investigated using optical and scanning microscopy and hardness and tensile testing. The results show that by increasing the applied strain, the Al/Ni/Cu multilayer composite converted from layer features to near a particle-strengthening characteristic. After the fifth ARB cycle, a composite with a uniform distribution of reinforcements (Cu, Ni, and SiC) was fabricated. The tensile strength of the composite increased from the initial sandwich structure to the first ARB cycle and then decreased from the first to the third ARB cycle. Upon reaching five ARB cycles, the tensile strength of the composite increased again. The variation in the elongation of the composite exhibited a tendency similar to that of its tensile strength. It is observed that with increasing strain, the microhardness values of the Al, Cu, and Ni layers increased, and that the dominant fracture mechanisms of Al and Cu were dimple formation and ductile fracture. In contrast, brittle fracture in specific plains was the main characteristic of Ni fractures. [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]