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Complex concentrated alloys (CCAs) are attracting considerable interest due to their potential applications under extreme conditions. This study focuses on two complex concentrated alloys, the FeAlCrV and the FeAlCrMo alloys, which already exhibited exceptional mechanical properties at high temperatures. In this regard, room temperature corrosion resistance and high-temperature oxidation were studied to investigate their potential applicability in harsh environments. It is shown that the corrosion resistance of both CCAs is much higher than that of AISI 304 and P91 steels in 0.5 M H2SO4 solution, while in 3.5% NaCl solution was comparable. On the contrary, high-temperature oxidation of CCAs was unsatisfactory, especially exceeding 700 °C. The intensive analysis of the formed oxide scales revealed that the protective oxide layer is not being formed at temperatures above 700 °C, primarily because of the occurrence of vanadium corrosion (FeAlCrV) and evaporation of Mo oxides (FeAlCrMo). The results of this study unambiguously showed the importance of studying oxidation properties at high temperatures parallel with the mechanical properties for the development of CCAs for cutting-edge technical applications.

Two novel ignition-resistant magnesium alloys, Mg-2Gd-2Y-1Ca and Mg-2Nd-1Y-1Ca, were prepared in the ultrafine-grain condition by equal channel angular pressing (ECAP). In addition, four commercial alloys—AZ31, AX41, AE42 and WE43—were prepared similarly as a reference. The microstructure, mechanical properties and ignition temperature were thoroughly investigated. Both novel alloys exhibited a mean grain size of ~1 µm and dense distribution of small secondary phase particles. The mechanical strength measured by the tensile deformation test showed that the novel alloys are much stronger (~290 MPa) than all commercial alloys except WE43. However, Ca segregation into the grain boundaries caused a significant decrease in ductility (

The effect of blocky to lamellar phase transformation on the microstructure and micro-texture of a Magnesium-Rare earth alloy containing long-period stacking order (LPSO) phases were examined comprehensively at the isothermal temperature of 400 °C via multiaxial forging. A very fine-grained microstructure with an average grain size of 1 μm was achieved after applying three multi-axial forging (MAF) passes. Particle stimulated nucleation (PSN) along with continuous dynamic recrystallizations (CDRX) due to the blocky LPSO phases were realized to be the main reasons for the achievement of such fine microstructure. The deformation-induced blocky to lamellar phase transformation began at 1/3 pass and expanded through the whole microstructure after the third pass. Such phase transformation was found to be initiated by the fragmentation of blocky phases. As a result of PSN and CDRX mechanisms, two new rare earth (RE) texture components of and || Transverse Direction (TD) were formed at the second MAF pass that led to a highly randomized deformation texture. Nevertheless, the continuous breakdown of blocky phases and their subsequent phase transformation to lamellar LPSO suppressed PSN at the third deformation pass. Hence, the formed RE texture components were disappeared which in turn increased the texture intensity at this deformation pass.

Powder metallurgy is a powerful method for the preparation of materials with superior properties. This work aimed to investigate the effect of powder size on the microstructure, mechanical, and corrosion properties of advanced WE43 (Mg-4Y-3REE-Zr) alloy prepared by spark plasma sintering (SPS). At the same time, the effect of HF pre-treatment of the powder on the properties of final compacted products is studied. Smaller powder particles yielded microstructure with more interfaces formed by Y2O3, or MgF2 and YF3. These interfaces work as barriers against corrosion, which greatly improves corrosion resistance. The suggested pre-treatment of powder in HF further reduced the corrosion rate of the compacted materials. On the contrary, fragile interfaces of YF3 decreased mechanical properties as the crack primarily propagates through these interfaces. The original powder containing the mixture of all powder fractions exerted the best combination of mechanical properties. Powder size has also shown to affect ignition temperature. The highest ignition temperature was measured for the finest powder fraction.

In this study, a novel severe plastic deformation technique referred to as rotational constrained bending (RCB) is introduced. A special constrained bending die, which imposes bending deformation to the billet during the first pass, was developed for repetitive processing of pre-extruded commercially pure Ti. Strain-induced microstructural changes were investigated by a special technique of automated crystal orientation mapping in TEM simultaneously with advanced X-ray line profile analysis. Plastic deformation distribution, imposed to the billets after a selected number of passes, was followed by precise microhardness mapping. Exceptional microstructure refinement was attained by the application of repetitive bending deformation. Average grain size decreased down to 400 nm, and the dislocation density increased by about 35 pct after ten passes. X-ray macrotexture measurements revealed the formation of a basal slip texture component commonly observed in HCP materials processed by equal channel angular pressing; however, exceeding four passes, a strong $$ \left\{ {11{\bar{2}}0} \right\} $$ fiber texture started to form. Mechanical testing in tension showed a significant increase in strength in the RCB-processed samples. The proof-stress and tensile strength increased by 30 and 15 pct after four passes, respectively. At a higher number of passes, the proof stress slightly decreased because of the texture softening.

V-pit defects in InGaN/GaN were studied by numerical simulations of the strain field and X-ray diffraction (XRD) reciprocal space maps. The results were compared with XRD and scanning electron microscopy (SEM) experimental data collected from a series of samples grown by metal–organic vapor phase epitaxy. Analysis of the principal strains and their directions in the vicinity of V-pits explains the pseudomorphic position of the InGaN epilayer peak observed by X-ray diffraction reciprocal space mapping. The top part of the InGaN layer involving V-pits relieves the strain by elastic relaxation. Plastic relaxation by misfit dislocations is not observed. The creation of the V-pits appears to be a sufficient mechanism for strain relaxation in InGaN/GaN epilayers.

The samples of polycrystalline cobalt were strained in tension in the second stage of work hardening in order to activate twinning. The identification of twins and their orientation was analyzed using electron backscatter diffraction. The study of twin variant selection was carried out based on two parameters, namely the Schmid factor (SF) and the geometric compatibility factor (m'). The results indicate that the grains contained the $$\left\{ {10\overline{1}2} \right\}$$ extension twins in most cases while the $$\left\{ {11\overline{2}1} \right\}$$ extension twin mode was present in few cases, as well. In the grains containing only one twin variant, the SF analysis correctly predicted the activated twins in most cases. In the grains with variant pairs in para-position, nearly half of the studied twins had the highest SF of all possible variants, which means that they followed the Schmid law. On the other hand, for twin pairs in meta- or ortho-position, a different behavior was observed. Twins in these configurations were selected rather by the strain compatibility criterion than by the Schmid law, as SF values of the activated twins were significantly lower than those of the twins in para-position. Of these two configurations, the ortho-position one is highly preferred. The combined analysis using SF and m' parameter, predicted the occurrence of specific twin modes and variants only partially. A local analysis considering the effect of neighboring grains should be developed to account for the cases where the two parameters fail to explain the occurrence of particular twins, which seems to be related to the presence of a high fraction of high-angle grain boundaries.

Sputter-deposited Zr/Nb nanoscale metallic multilayers with a periodicity of 27 (thin) and 96 nm (thick) were subjected to Cu+implantation with low and high fluences and then studied using various experimental techniques in combination with DFT calculations. After Cu+ implantation, the thinner multilayer exhibited a tensile strain along c-axis in Nb layers and a compressive strain in Zr layers, while the thicker multilayer showed a compressive strain in both layers. The strain is higher in the thin multilayer and increases for higher fluences. We developed a mathematical method for the fundamental understanding of the deformation mechanisms in metallic multilayers subjected to radiation damage. In the model, the cumulative strain within a layer is described as the combination of two contributions coming from the interfacial region and the inner region of the layers. The semi-analytical model predicts that the interfacial strain is dominant and extends over a certain region around the interface. Predictions are well supported by ab-initio calculations which show that in the vicinity of the interface and in the Zr side, vacancies and interstitials (low energy barriers) exhibit high mobility compared to the Nb side, thus resulting in a high recombination rate. As a consequence, less strain occurs in the Zr side of the interface compared to the Nb side. The density and distribution of various types of defects along the ion profile (low and high damaged regions) are obtained by combining DFT results and the predictions of the model.

The surface structure of medical implants and their chemical state are extremely important for their lifetime and reliability. There are problems with the degradation of NiTi implants due to structural fatigue, localized tribo-corrosion, and inconsistent hemocompatibility. These issues potentially can be solved by surface texturing by controlled short laser pulse treatments with a multibeam approach explored in this study. One of the unique surface textures in nanoscale is represented by introducing laser induced periodic surface structures (LIPSS) into the implant surface. The LIPSS formation involves the excitation of surface plasmon polaritons and material surface reorganization. Ripples with periodicity less than 1 ?m along with the catalytic activity of oxide surface with "rutile nanohairs" can significantly reduce bacterial film adhesion while promoting surface endothelialization and hemocompatibility. The morphological texturing of the surface allows for tuning the wetting properties from extreme hydrophobicity to hydrophilicity. Reduction of friction and wear of material surfaces can be achieved by introducing textures that reduce the contact friction area. The geometry of the LIPSS and dimples maintains an adhesive film of liquid among moving parts. Short laser "beam-shaped" pulses were applied in this work to NiTi surfaces. The results indicate that LIPSS processing of NiTi surface with controlled height profiles and periodicity gives rise to chemisorbed hydrocarbon molecules on rutile oxide layer, which leads to super-hydrophobicity and a beneficial antibacterial effect. Ultrashort laser pulse micromachining does not affect the microstructure and martensitic phase transformation. The corrosion resistance of LIPSS textured NiTi surface is not degraded, and the process reduces friction area and maintains an adhesive film of liquid between the moving parts.

Colorectal cancer is one of the most common cancers in Europe and the world. Cancer treatments have side effects and cause significant deterioration of the patient’s nutritional status. Patient malnutrition may worsen the health condition and prevent the deliberate effects of the therapy. The aim of this review was to describe the available data about clinical nutrition in colorectal cancer patients. A large proportion of colorectal cancer patients suffer from malnutrition, which negatively affects the survival prognosis, quality of life, and oncological therapy. Therefore, monitoring nutritional status during the treatment is essential and can be used to arrange proper nutritional therapy to enhance patient responses, prevent side effects, and shorten recovery time. The principles of nutrition during anticancer therapy should mainly consider light and low-fat foods, the exclusion of lactose and gluten-containing foods in certain cases, or the introduction of special dietary products such as oral nutrition supplements and it should be tailored to patients’ individual needs.

This study deals with monitoring of Zn layer heterogeneity on the flange of steel road barriers using magnetic measurements. The Barkhausen noise technique is employed for such purpose, and parameters extracted from Barkhausen noise signals are correlated with the true thickness of the Zn layer. The true values of the Zn layer were obtained from the metallographic images, as well as the thickness gauge CM-8825FN (Guangzhou Landtek Instruments Co. Ltd., Guangzhou, China) device. It was observed that the diffusion region lies below the Zn protective layer, which makes the thickness of the Zn layer obtained from the CM-8825FN device thicker than that measured on the metallographic images. For this reason, the chemical gradient of Zn below the Zn layer can be reported, and it affects Barkhausen noise emission. Barkhausen noise decreases along with increasing thickness of the Zn layer, and Barkhausen noise envelopes are shifted to stronger magnetic fields. The number of strong MBN pulses drops down with the increasing thickness of Zn coating at the expense of the increasing number of the weak MBN pulses. The thickness of Zn coating can be polluted by the solidification of Zn melt after galvanizing. The presence of the diffusion layer dims the contrast between ferromagnetic and paramagnetic phases.

This paper presents mechanical-acoustic study of samples made from electroporcelain mixture (type C 130) under five different compression pressures from 70 MPa up to 110 MPa. The samples were studied using the impulse excitation technique, thermodilatometry, thermogravimetry, and acoustic emission in the temperature interval from 1100 to 50 °C. X-ray powder diffraction was used for the determination of crystalline phases. Microstructure observations using scanning electron microscopy revealed small differences between compression pressures 70 MPa and 110 MPa. The results of impulse excitation technique show that using a higher compression pressure an increase in Young’s modulus is observed. The values of Young’s modulus after cooling to room temperature reach 18.4 GPa, 19.5 GPa, 19.7 GPa, 19.9 GPa, and 20.1 GPa for the compression pressure of 70 MPa, 80 MPa, 90 MPa, 100 MPa, and 110 MPa, respectively. The results also show that the acoustic emission activity starts at solidification of the glassy phase in the temperature interval of 800–700 °C.

This paper investigates surface state after turning of the high tempered bearing steel 100Cr6 with a hardness of 40 HRC. White layer (WL) thickness and its microhardness, as well as surface roughness, are investigated as a function of tool flank wear VB as well as cutting speed v(c). The mechanical and thermal load of the machined surface were analysed in order to provide a deeper insight into their superimposing contribution. Cutting energy expressed in terms of cutting force was analyses as that consumed for chip formation F-gamma and consumed in the flank wear land F-alpha. It was found that the mechanical energy expressed in terms of the shear components of the F-alpha grows with VB, converts to the heat and strongly affects the thickness of the re-hardened layer. Furthermore, the superimposing contribution of the heat generation and its duration in the VB region should also be taken into account. It was also found that the influence of VB predominates over the variable cutting speed. Web of Science 15 5 art. no. 1718

In the field of magnesium-based degradable implantable devices, the Mg-Y-RE-Zr alloying system (WE-type) has gained popularity due to its satisfying degradation rate together with mechanical strength. However, utilization of RE and Zr in the WE-type alloys was originally driven to improve Mg-based alloys for high-temperature applications in the industry, while for medical purposes, there is a question of whether the amount of alloying elements may be further optimized. For this reason, our paper presents the Mg-3Y (W3) magnesium alloy as an alternative to the WE43 alloy. This study shows that the omission of RE and Zr elements did not compromise the corrosion resistance and the degradation rate of the W3 alloy when compared with the WE43 alloy; appropriate biocompatibility was preserved as well. It was shown that the decrease in the mechanical strength caused by the omission of RE and Zr from the WE43 alloy could be compensated for by severe plastic deformation, as achieved in this study, by equal channel angular pressing. Ultrafine-grained W3 alloy exhibited compression yield strength of 362 ± 6 MPa and plastic deformation at maximum stress of 18 ± 1%. Overall, the early results of this study put forward the motion of avoiding RE elements and Zr in magnesium alloy as a suitable material for biodegradable applications and showed that solo alloying of yttrium is sufficient for maintaining desirable properties of the material at once.

Aluminium steel clad materials have high potential for industrial applications. Their mechanical properties are governed by an intermetallic layer, which forms upon heat treatment at the Al-Fe interface. Transmission electron microscopy was employed to identify the phases present at the interface by selective area electron diffraction and energy dispersive spectroscopy. Three phases were identified: orthorhombic Al5Fe2, monoclinic Al13Fe4 and cubic Al19Fe4MnSi2. An effective interdiffusion coefficient dependent on concentration was determined according to the Boltzmann–Matano method. The highest value of the interdiffusion coefficient was reached at the composition of the intermetallic phases. Afterwards, the process of diffusion considering the evaluated interdiffusion coefficient was simulated using the finite element method. Results of the simulations revealed that growth of the intermetallic phases proceeds preferentially in the direction of aluminium.

Aluminium steel clad materials have high potential for industrial applications. Their mechanical properties are governed by an intermetallic layer, which forms upon heat treatment at the Al-Fe interface. Transmission electron microscopy was employed to identify the phases present at the interface by selective area electron diffraction and energy dispersive spectroscopy. Three phases were identified: orthorhombic Al5Fe2, monoclinic Al13Fe4 and cubic Al19Fe4MnSi2. An effective interdiffusion coefficient dependent on concentration was determined according to the Boltzmann–Matano method. The highest value of the interdiffusion coefficient was reached at the composition of the intermetallic phases. Afterwards, the process of diffusion considering the evaluated interdiffusion coefficient was simulated using the finite element method. Results of the simulations revealed that growth of the intermetallic phases proceeds preferentially in the direction of aluminium.

The magnesium AZ31 alloy was swaged with rotary pressure with the aim of redefining the microstructure and improving mechanical and fatigue properties. The rotary swaging process and subsequent ageing improved the yield stress in tension and compression. In the present study, the investigation was focused on fatigue behaviour. The samples were cycled in a symmetric regime with a frequency of 35 Hz. A dependence of the stress amplitude on the number of cycles up to the fracture was estimated. The microstructure of the samples and fracture surfaces was analysed with a scanning electron microscope. The fatigue process was influenced by the pronounced texture formed in the swaging process. The fatigue properties of the swaged samples improved substantially—the endurance limit based on 107 cycles was approximately 120 MPa—compared to those of the cast alloy. The analysis of the fracture surfaces showed a transcrystalline fatigue fracture.

Monitoring of corrosion extent is critical in bridge operation and civil buildings. Reducing the effective cross-sectional area of components can redistribute the stress state and increase the true stress in the critical parts of civil structures. Unexpected rupture of bodies can occur as a result of their over-stressing. However, it is not possible to take relevant samples from these structures for a laboratory analysis during their lifetime. For this reason, this study investigates the potential of magnetic Barkhausen noise analysis for real-time corrosion extent monitoring. This study demonstrates that Barkhausen noise emission drops down along with an increasing degree of corrosion of steel S460MC. Progressive and remarkable decrease of Barkhausen noise and alteration of extracted features result from increasing surface roughness and superimposing influence of the increasing thickness of the near-surface layers containing mainly iron oxides. Furthermore, it was found that corrosion on the surface also alters the relation between tensile stress and Barkhausen noise within the interaction volume.

The $5f$-based ferromagnet $\mathrm{U}{\mathrm{Ga}}_{2}$ with the Curie temperature ${T}_{\mathrm{C}}=125\phantom{\rule{0.16em}{0ex}}\mathrm{K}$ was investigated by x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) experiments at the $\mathrm{U}--{M}_{4,5}$ and Ga--K edges. The position of the $\mathrm{U}--{M}_{4}$ white line, determined in the high-energy resolution fluorescence detection XAS, suggests that $\mathrm{U}{\mathrm{Ga}}_{2}$ is neither a localized $5{f}^{2}$ nor an itinerant system with $5f$ occupancy close to ${n}_{5f}=3$. The analysis of the acquired ${M}_{4,5}$ XANES and XMCD spectra indicates the $5f$ occupancy close to 2.5 and a large orbital magnetic moment of the uranium $5f$ states (3.18 ${\ensuremath{\mu}}_{\mathrm{B}}$) that is partly compensated by the antiparallel spin moment (1.31 ${\ensuremath{\mu}}_{\mathrm{B}}$). Thus, the total $5f$ magnetic moment of 1.87 ${\ensuremath{\mu}}_{\mathrm{B}}$ is obtained, which is smaller than the known bulk magnetization of 3.0 ${\ensuremath{\mu}}_{\mathrm{B}}$ per formula unit, while the magnetic moments of the Ga atoms are negligible. Several methods based on density-functional theory were applied and the obtained results were compared with XAS spectral features, the Sommerfeld coefficient of the electronic specific heat, and the size of the U moments and $5f$ occupancies. A clear correlation is revealed between the $\mathrm{U}--{M}_{4}$ white-line position of three metallic uranium compounds and the calculated uranium ionicity. It is demonstrated that only electronic structure methods taking appropriate care of orbital magnetism and related atomic multiplet effects can successfully describe all considered properties.