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In view of a large number of people infected with Helicobacter pylori (H. pylori) with great harm followed, there is an urgent need to develop a non-invasive, easy-to-operate, and rapid detection method, and to identify effective sterilization strategies. In this study, highly specific nanoprobes with nanozyme activity, Ag@Pt nanoparticles (NPs) with the antibody, were utilized as a novel lateral flow immunoassay (LFIA). The optical label (Ag@Pt NPs) was enhanced by the introduction of the chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) and compared with a gold nanoparticles (Au NPs) optical label. Under the optimal condition, Ag@Pt-LFIA and TMB-enhanced Ag@Pt-LFIA for H. pylori were successfully established, two of which were over twofold and 100-fold more sensitive than conventional visual Au NP-based LFIA, respectively. Furthermore, Ag@Pt NPs with the antibody irradiated with NIR laser (808 nm) at a power intensity of 550 mW/cm2 for 5 min exhibited a remarkable antibacterial effect. The nanoprobes could close to bacteria through effective interactions between antibodies and bacteria, thereby benefiting photothermal sterilization. Overall, Ag@Pt NPs provide promising applications in pathogen detection and therapeutic applications. [ABSTRACT FROM AUTHOR]

As promising energy-storage devices, zinc–air batteries (ZABs) exhibit slow reaction kinetics for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) occurring at their electrodes. High-performance bifunctional catalysts must thus be synthesized to accelerate the reversible conversion of oxygen and improve the rate and overall performance of ZABs. Herein, we reported the promising prospects of self-supported composite electrodes composed of wood-derived carbon (WDC) and bimetallic cobalt-iron alloys/oxides (CoFe-CoFe2O4@WDC) as efficient electrocatalysts for alkaline ORR/OER. WDC provided a favorable three-phase interface for heterogeneous reactions owing to its layered porous structure and genetic stability, thereby enabling mass diffusion and improving reaction kinetics. The CoFe2O4 spinel surface was reduced to bimetallic CoFe alloy to form abundant heterostructure interfaces that promote electron transfer. Under alkaline conditions, the optimized composite electrode exhibited a remarkable high half-wave potential of 0.85 V and an exceptionally low overpotential of 1.49 V. It also exhibited stable performance over an impressive 2340 cycles in a ZAB. Theoretical calculations also confirmed that the heterointerface addresses the issue of proton scarcity throughout the reaction and actively facilitates the creation of O–O bonds during the reversible transformation of oxygen. This study introduces a new concept for developing bifunctional and efficient electrocatalysts based on charcoal and encourages the sustainable and high-value use of forest biomass resources. Highlights: Water dissociation was regulated to provide proton for smooth response under alkaline conditions and accelerate the conversion of *O2 to *OOH. The alloy surface formed CoFe oxyhydroxide in the OER voltage range, and the adsorption capacity of intermediates was adjusted to facilitate O–O bond formation. The d-band center moved downward due to interface electron interaction, modifying the binding ability of intermediates. [ABSTRACT FROM AUTHOR]

• The microstructure of Mg-Al-Sn-RE anode is tailored via friction stir processing. • The processed anode has fine grains, low dislocation density, and weak orientation. • This unique anode structure boosts the voltages and capacities of Mg-air battery. • The discharge mechanism corresponding to the unique anode structure is analysed. Constructing the magnesium alloy with fine grains, low density of dislocations, and weak crystal orientation is of crucial importance to enhance its comprehensive performance as the anode for Mg-air battery. However, this unique microstructure can hardly be achieved with conventional plastic deformation such as rolling or extrusion. Herein, we tailor the microstructure of Mg-Al-Sn-RE alloy by using the friction stir processing, which obviously refines the grains without increasing dislocation density or strengthening crystal orientation. The Mg-air battery with the processed Mg-Al-Sn-RE alloy as the anode exhibits higher discharge voltages and capacities than that employing the untreated anode. Furthermore, the impact of friction stir processing on the electrochemical discharge behaviour of Mg-Al-Sn-RE anode and the corresponding mechanism are also analysed according to microstructure characterization and electrochemical response. [ABSTRACT FROM AUTHOR]

AB 3 -type La-Mg-Ni-based hydrogen storage alloys are known for their high electrochemical hydrogen storage capacity. However, their practical application has been hindered by fast capacity degradation. Herein, we managed to improve their cycle life by synchronizing the hydrogen absorption/desorption behaviors of [A 2 B 4 ] and [AB 5 ] subunits based on a series of AB 3 -type single-phase La 0.60 R 0.12 Mg 0.28 Ni 3 (R = La, Pr, Nd, Gd) superlattice alloys. This is achieved by the preferable occupation of Pr, Nd and Gd in [A 2 B 4 ] subunits rather than [AB 5 ] subunits compared to La, which decreases the volume difference between [A 2 B 4 ] and [AB 5 ], significantly reducing the mismatch between [A 2 B 4 ] and [AB 5 ] during hydrogen absorption/desorption. Resultantly, the microstrain of the R = Gd alloy is only half that of the R = La alloy, leading to enhanced anti-pulverization and anti-oxidation/corrosion resistance, as well as an improved cycle stability. The S 100 of the R = Gd alloy is more than 15 % higher than the R = La alloy. Moreover, the plateau pressure is adjusted to a proper level, enabling an increase in the high-rate dischargeability (HRD 1500) from 53.6 % (R = La) to 66.4 % (R = Gd). This work provides impressive insights into developing high-performance superlattice hydrogen storage alloys. [Display omitted] • Single-phase AB 3 -type superlattice alloys with different RE elements are acquired. • V [A2B4] and V [AB5] are equalized by selective occupation of RE elements. • H 2 absorption/desorption of [A 2 B 4 ] and [AB 5 ] subunits are synchronized. • Not only is cycle stability greatly enhanced, but HRD is also improved. [ABSTRACT FROM AUTHOR]

The co-deposition behavior of Co(II) and Mo(VI) and Co–Mo electro-crystallization mechanism in ethylene glycol (EG) are recorded using cyclic voltammetry and chronoamperometry. These results indicate that the Co–Mo co-deposition is representative induced deposition; Co(II) species can facilitate Co–Mo co-deposition, inversely, Mo(VI) species can inhibit Co(II) reduction and the effect can be enhanced as Mo(VI) concentration increases. Additionally, Co–Mo co-deposition in EG takes place through an instantaneous nucleation and diffusion-controlled three-dimensional growth mechanism. Co–Mo deposits with various Mo contents and different microstructures can be obtained from the EG solution. SEM micrographs present that the Co–Mo deposits with 1.56 wt% Mo present a pure pompon microstructure. Benefiting from the composition engineering by alloying with Mo, as well as the simultaneous presence of a suitable pompon structure, Co–Mo deposits with 1.56 wt% exhibits prominent electrocatalytic durability and activity with a η10 of 84 mV for HER in a 1.0 M KOH. [ABSTRACT FROM AUTHOR]

The corrosion resistance of FeCoNiCr high-entropy alloy deposits was investigated upon being prepared by current electrodeposition. The coatings were co-deposited in an electrolyte of an aqueous ferrous, cobalt, nickel, and chromium sulfates solution. Energy dispersive spectrometry analysis demonstrated that all four elements were co-deposited successfully. At the same time, the results from SEM indicate that the surface of the coating exhibits a granular morphology, with uniform density and no presence of cracks, with sizes ranging from 500 nm to 5 μm. Furthermore, X-ray diffraction patterns enunciated that the as-deposited coatings were amorphous. The polarization curves of the FeCoNiCr high-entropy alloy coating were measured by an electrochemical workstation in 3.5 wt.% NaCl, 1 mol·L−1 H2SO4 and 1 mol·L−1 NaOH solutions. The results revealed that the coating exhibited excellent corrosion resistance. The corrosion mechanism of the FeCoNiCr high-entropy alloy coating was analyzed in different environments. Moreover, the scratch testing method was employed to determine the alloy adhesion on the substrate, with higher values obtained for the FeCoNiCr alloy. [ABSTRACT FROM AUTHOR]

Stress annealing is utilized for enhancing the magnetic softness of Fe83–xCoxB10Si3C3P1 (x = 0–16) amorphous alloys with saturation polarization up to 1.75 T. All of the stress-annealed alloys exhibit improved soft-magnetic properties, including low coercivity of 1.8–2.2 A/m, low core loss of 0.09–0.11 W/kg at 1.0 T and 50 Hz, and high permeability of 27,000–33,200 at 5 A/m and 1 kHz. Stress annealing induces longitudinal magnetic anisotropy and facilitates the annihilation of free volume, leading to pinning-free domain wall motion, and thus the enhanced magnetic softness. The induced magnetic anisotropy relates to the constrained elastic elongation introduced by stress annealing. The stress-annealed Fe83–xCoxB10Si3C3P1 (x = 0–16) amorphous alloys exhibit excellent magnetic softness, sheding light on the designing and processing of amorphous soft magnetic alloys with high saturation polarization. [ABSTRACT FROM AUTHOR]

The theory of heterogeneous nucleation was initially developed as a part of condensed matter physics, and later it was used as an important engineering tool to design metallurgical processes. This success has led to wide applications of the theory in metallurgical practice. For example, engineering heterogeneous nucleation in ductile iron has been used to reduce shrinkage defects, suppress cementite formation, and modify the size and shape of microstructural constituencies. This demonstrates how theoretical knowledge could benefit industry practice. This overview aims to summarize the authors' published studies in co-authorship with colleagues and students, which covers different aspects of engineering heterogeneous nucleation in multiphase cast alloys. Several approaches for engineering heterogeneous nucleation using thermodynamic simulation as well as practical methods for improving efficiency of nucleation using the co-precipitation technique and a local transient melt supersaturation are suggested. Automated scanning electron microscopy/energy-dispersive X-ray (SEM/EDX) analysis and high-resolution transmission electron microscopy (TEM) were used to verify the simulation predictions. Practical examples of controlling microporosity shrinkage in cast irons with spheroidal graphite are presented to illustrate the power of engineering heterogenous nucleation. [ABSTRACT FROM AUTHOR]

Ni–Fe alloy foils for wireless charging have been prepared by electrodeposition from a sulfate plating solution at different bath temperatures. Systematic investigations have been conducted on the structure and composition of Ni–Fe alloy foils. The dependence of magnetic properties on bath temperatures has also been explored. The results show that with the bath temperature increasing, the (200) texture intensity, Ni mass fraction, and grain size of the Ni–Fe alloy foils gradually increase. In addition, Ni–Fe foils prepared at 70 °C have lowest coercivity, highest real part of the complex permeabilities (μ′) and large μ′Q (Q = μ'/μ"). Meanwhile, the application of Ni–Fe alloy foils for wireless charging has been investigated. It is found that adding a Ni–Fe alloy foils would effectively enhance coupling coefficient (k) for wireless charging, which benefits from the alloy's higher μ′ and smaller coercivity. When the bath temperature is 70 °C, k value can reach 0.64, which is comparable to conventional ferrite products. This work not only reveals the effect of bath temperature on the composition, structure, and magnetic properties of Ni–Fe alloy foils, but also offers novel insights into the application of Ni–Fe alloys foils for wireless charging. [ABSTRACT FROM AUTHOR]

A multi‐modal serum profiling platform holds promise for precision diagnosis of diseases. Still, advanced tools are in demand to deliver the multi‐modal serum profiling. Herein, a bimodal spectrometric protocol is designed for stoke serum profiling using an alloy platform, by integrating label‐free surface‐enhanced Raman spectroscopy (SERS) and laser desorption/ionization mass spectrometry (LDI‐MS). The PdAu@Au concave cube with a wide localized surface plasmonic resonance (LSPR) range simultaneously enhances the signals from SERS and LDI‐MS, enabling high‐throughput co‐detection of vibrational and metabolic fingerprints of 0.1 µL serum in 2 min with simple pretreatment. Further, a dual‐fingerprints screening model of stroke is constructed, by adaptive machine learning with a programming nonlinear fitting model. The area under the curve are 0.949 (0.917–0.977, 95% confidence interval (CI)) and 0.911 (0.812–0.984, 95% CI), in the discovery and validation cohorts, respectively. Finally, five metabolites are identified that correlated to SERS signals and mapped the relevant pathways. This study features high performance in terms of throughput, speed, sample volume, and accuracy, providing new insight into the construction of multiplexed characterization platforms for precision diagnostic. [ABSTRACT FROM AUTHOR]

Heat treatment is effective in reducing moisture absorption and improving the dimensional stability of wood. Low point metal alloy (LMPA) is characterized by high thermal conductivity and large surface tension and can be used as a liquid heat medium for heat treatment. To investigate the effects of liquid and gaseous heat medium on the hygroscopicity, dimensional stability, and chemical structure of heat-treated wood, LMPA and moist air were used as the heating medium during the heat treatment at 140 °C, 170 °C, and 200 °C for 2 h. The results indicated that LMPA heat treatment effectively improved the dimensional stability of wood by increasing the actual heat treatment temperature and reducing the preheating time of the wood. LMPA heat treatment at 200 °C decreased the radial, tangential, and volumetric swelling coefficients of wood by 62, 55, and 56%, respectively. Compared with moist air heat treatment, the radial, tangential, and volumetric swelling coefficients of the wood were reduced by 37, 27, and 38%, respectively. Chemical analyses via attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD) demonstrated that the LMPA heat treatment increased the degradation of hemicellulose and reduced the number of hygroscopic groups, resulting in higher crystallinity and enhanced dimensional stability. Hence, LMPA heat treatment can effectively resolve the poor thermal degradation due to prolonged preheating stage and high energy consumption associated with external power for forced convection during the conventional heat treatment using a gaseous heat medium. [ABSTRACT FROM AUTHOR]

Twinning-detwinning (TDT) behavior in a strongly basal-textured Mg-Li alloy during two-step compression (RD)-compression (ND) process was investigated using quasi-in-situ EBSD. TDT behavior and TDT variants selection were statistically discussed with the loading path for the first time. Non-Schmid twinning behavior was observed in the first step compression, owing to the local stress fluctuations by neighboring twins; in contrast, Schmid's law well predicted the detwinning variants selection. This asymmetrical TDT behavior was first investigated to date related with the strong basal texture and loading path. Besides, with the progress of compression, Schmid factors for twinning demonstrated a decreasing tendency; however, those for detwinning during the second step displayed an abnormally increasing trend, fundamentally stemming from prior twinning behavior. [ABSTRACT FROM AUTHOR]

The interdiffusion behavior of ternary face-centered-cubic (fcc) Al-Co-Cr alloys has been studied by the diffusion-couple technique and CALculation of PHAse Diagram (CALPHAD) approach. The composition profiles of the fcc Al-Co-Cr diffusion couples at 1000 and 1200 °C were measured by using electron probe microanalysis (EPMA), followed by the extraction of interdiffusion coefficients through the Whittle-Green method. Based on the available thermodynamic description and diffusion coefficients in the literature as well as the experimental data obtained in the present work, the atomic mobilities of Al, Co, and Cr in fcc Al-Co-Cr alloys were assessed by means of the CALPHAD method. The diffusion coefficients, composition profiles and diffusion paths of fcc Al-Co-Cr alloys were calculated by adopting the atomic mobilities assessed in the present work, reaching a good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

In this paper, we present the synthesis, first hydrogenation kinetics, thermodynamics and effect of cycling on the hydrogen storage properties of a V 0.3 Ti 0.3 Cr 0.25 Mn 0.1 Nb 0.05 high entropy alloy. It was found that the V 0.3 Ti 0.3 Cr 0.25 Mn 0.1 Nb 0.05 alloy crystallizes in body-centred cubic (BCC) phase with a small amount of secondary phase. The first hydrogenation is possible at room temperature without incubation time and reaches a maximum hydrogen storage capacity of 3.45 wt%. The pressure composition isotherm (P–C–I) at 298 K shows a reversible hydrogen desorption capacity of 1.78 wt% and a desorption plateau pressure of 80.2 kPa. The capacity loss is mainly due to the stable hydride with the desorption enthalpy of 31.1 kJ/mol and entropy of 101.8 J/K/mol. The hydrogen absorption capacity decreases with cycling due to incomplete desorption at room temperature. The hydrogen absorption kinetics increases with cycling and the rate-limiting step is diffusion-controlled for hydrogen absorption. [Display omitted] • V 0.3 Ti 0.3 Cr 0.25 Mn 0.1 Nb 0.05 high entropy alloy with BCC phase was prepared. • First hydrogenation of the alloy is without incubation time at room temperature. • Maximum hydrogen storage capacity of the alloy reaches 3.45 wt%. • Cycling performance of the high entropy alloy is investigated. • Structure evolution after hydrogen desorption and pumping is studied. [ABSTRACT FROM AUTHOR]

The poor tribological properties of Ti alloys limit their infield applications under sliding conditions. In this study, the surface of a Ti–6Al–4V alloy was coated with pure Al using a hot dipping process. The interface between coated pure Al and Ti–6Al–4V was characterized after the hot dipping and subsequent heat treatment. The effects of both processes on the interface microstructure and the formation mechanism of the Ti/Al interface were investigated. A metallurgical bond was established at the interface between Al coating and Ti–6Al–4V substrate following the hot dipping. Subjecting samples to heat treatment resulted in oxidation of Al coating and transforming into alumina (Al2O3) while Ti–Al intermetallic compounds were formed. Microhardness and tribological properties of the Al coated Ti–6Al–4V sample were measured. When the heat treatment temperature was 750 °C, the microhardness reached the maximum of about 500 HV. The overall trend for the friction coefficient showed to decrease first, and then increased and fluctuated around a constant value. The friction coefficient of the sample subjected to heat treatment at 750 °C for 6 hours remained low. The optimized process parameters can be summarized as hot dipping at 700 °C for 15 mins, followed by a heat treatment at 750 °C for 6 hrs. This process can improve the wear resistance of Ti–6Al–4V alloy through the formation of block-like TiAl3 phase and oxides. The results were helpful and could form a basis for further researches on enhancing the tribological property of Ti alloys. [ABSTRACT FROM AUTHOR]

Corrosion and wear play significant roles in the aseptic loosening of artificial hip joints for the long‐term service. In this present study, tribo‐corrosion tests were carried out through a reciprocating ball‐on‐plate system to evaluate the corrosion and wear properties of CoCrMo, Ti6Al4V and Ti15Mo alloys in a simulated body fluid (SBF) solution. It was found that the tribo‐corrosion behaviours of CoCrMo/Al2O3 and Ti15Mo/Al2O3 systems had significant wear‐corrosion synergistic interaction, and wear‐induced corrosion was dominant. For Ti6Al4V/Al2O3 systems, their wear mechanism under SBF lubrication was a combination of abrasive, adhesive and fatigue wear. While the wear mechanism of the Ti15Mo/Al2O3 system under synergistic interaction was a combination of abrasive and adhesive wear. Finally, it was suggested that the Ti15Mo alloy would be the better alternative for metal implant applications compared with the CoCrMo alloy for the consideration of both wear and potential poisonous ions such as Co(III) and Cr(VI). [ABSTRACT FROM AUTHOR]

We reported the modification of a NiAl-layered double hydroxide (LDH) by loading well-dispersed CoPd alloys through a NaBH4 reduction method. The modified NiAl-LDH achieved 14.5-fold and 2.1-fold improvements of the H2 and CO evolution rates and an applicable ratio of H2/CO (nearly 1 : 1) under visible light (λ > 420 nm). This study revealed the potential of alloys to adjust the H2/CO ratio and enhance syngas production for LDHs for the first time. [ABSTRACT FROM AUTHOR]

The difficultness of Ga inclusion in conventional CuInGa plating can be solved by metal-oxide/hydroxide deposition. However, the selenization process with the oxide precursor is very difficult, because of the strong electronegativity of oxygen. In this work, we proposed a strategy of Cu(InGa)Se2 thin films manufacture with selenization employing mixed precursor. The precursor consists of CuIn alloy and CuGa oxide/hydroxide, and deposited by electrodeposition as the sources of Cu, In and Ga. Then, the selenization process is performed in the mixed atmosphere of selenium vapor, hydrogen and argon. Meanwhile, we investigated the structural, optical and electrical properties of the prepared Cu(InGa)Se2 thin films, and it implied both the deposition potential and the subsequent selenization time impact the structure and morphology of the thin films. The co-deposition of CuGa oxide/hydroxide improved the Ga deposition ratio, and it exhibited dendrite growth with large deposition potential. The subsequent selenization results in the transformation from the precursor to CuInSe2 and Cu(InGa)Se2, as well as, the long selenization time lead to the oxygen concentration decreasing and high Ga concentration in CuInSe2 films. In the end, with a potential of −0.5 V versus Ag/AgCl electrode, the film had a photo-generated current density of 0.05 mA/cm2, and the CIGS solar cell achieved a conversion efficiency of 1.85%. [ABSTRACT FROM AUTHOR]

In this work, the crystal structure and hydrogen storage properties of V 35 Ti 30 Cr 25 Fe 10 , V 35 Ti 30 Cr 25 Mn 10 , V 30 Ti 30 Cr 25 Fe 10 Nb 5 and V 35 Ti 30 Cr 25 Fe 5 Mn 5 BCC-type high entropy alloys have been investigated. It was found that high entropy promotes the formation of BCC phase while large atomic difference (δ) has the opposite effect. Among the four alloys, the V 35 Ti 30 Cr 25 Mn 10 alloy shows the highest hydrogen absorption capacity while the V 35 Ti 30 Cr 26 Fe 5 Mn 5 alloy exhibits the highest reversible capacity. The cause of the loss of desorption capacity is mainly due to the high stability of the hydrides. The higher room-temperature desorption capacity of the V 35 Ti 30 Cr 25 Fe 5 Mn 5 alloy is due to higher hydrogen desorption pressure. After pumping at 400 °C, the hydrides can return to the original BCC structure with only a small expansion in the cell volume. [Display omitted] • A series of high entropy alloys (HEAs) with BCC phase structure are prepared. • High Δ S promotes the formation of BCC phase while δ has the opposite effect. • HEAs with high BCC phase ratio show high H 2 absorption and desorption capacity. • The cause of the loss of hydrogen desorption capacity is revealed. [ABSTRACT FROM AUTHOR]

Strength and hardness of metallic materials are reported to correlate in a specified form. Among various equations, yield strength is generally converted from Vickers hardness (HV) via a three‐time relation due to the simple and nondestructive nature of hardness testing. Herein, a through literature review is made and data of strength and HV for face‐centered cubic (FCC) and body‐centered cubic (BCC) high‐entropy alloys (HEA) are collected. The yield strength and HV visibly deviate from the three‐time relation, but the ultimate tensile strength and HV roughly follow the three‐time relation. New linear relationships, which are universally applied to convert HV to yield strength and ultimate tensile strength, are proposed. [ABSTRACT FROM AUTHOR]

In heat-resistant Al–Cu–Mg–Ag alloys, the presence of AgMg segregation layer on Ω phase ensures its high thermal stability. It was reported Ω precipitation would be inhibited when Si was added such that the Mg/Si mass ratio was lower than 2. However, in this work, it has been proved the notable increase in Ag content from 0.5% to 0.8% could still promote precipitation of Ω besides θ′ in an Al–Cu–Mg–Ag–Si alloy with a Mg/Si mass ratio around 1.7. The key point is to obtain an Ag/Mg excess atomic ratio greater than 1 under the premise of W(Mg)/W(Si) > 1.4 in the supersaturated solid solution, where Mg excess denotes the remaining Mg solutes after the formation of C/L phase. Although the fine precipitation of Ω in the 0.8 Ag alloy increases the total volume fraction of precipitates and yield strength, their quick coarsening at high temperature leads to a more pronounced strength loss. Such a comparison reveals the fully enveloped Ω precipitate is less stable than the θ′ precipitate with multiple interface phases. These findings update our knowledge on the systematic composition design for tunning Ω/θ′ precipitates' ratio and properties of Al–Cu–Mg–Ag–Si alloys. [ABSTRACT FROM AUTHOR]

A new generation aluminum alloy strengthened by T-Mg 32 (AlZn) 49 phase has been created in the last decade based on 5xxx series Al-Mg alloy modified with the idea of precipitation strengthening in 7xxx series alloys, promising to overcome the trade-off between corrosion performance and mechanical properties. Herein, a novel retrogression and thermo-mechanical treatment (RTMT) was designed to further enhance comprehensive properties of the T-phase strengthened alloy through combining strain-hardening and precipitation-hardening. By comparing with traditional peak-aging treatment, retrogression and re-aging treatment, and final thermo-mechanical treatment, RTMT achieves an increase in tensile and yield strength of the alloy to 587.9 MPa and 537.5 MPa, respectively, and a significant reduction in the maximum intergranular corrosion depth to 37.5 μm simultaneously. Microstructure observation indicates that the enhanced interaction between the regulated precipitates and dislocations introduced during deformation is the key to synergistic improvement of corrosion and mechanical properties. The processing technology can be extendable to other age-hardening alloy systems for further development and application. • The RTMT significantly increases the IGC resistance and strength of Al-Mg-Zn alloy simultaneously. • The regulated element distribution at grain boundaries plays a key role in the improvement of corrosion resistance. • The interaction between precipitates and dislocations in alloys treated by RTMT is clarified. [ABSTRACT FROM AUTHOR]

Amorphous metal alloy catalysts have attracted even-increasing attention owing to their high activity and selectivity. However, they are mainly prepared in ultrafine nanoparticles, which are easily gathered and challenging to separate. In this work, mesoporous Ru(Co, Ni)B bimetallic amorphous alloy catalysts with magnetic properties that can be easily recovered were synthesized via surfactant self-assembly. The as-prepared Ru 1% CoB catalyst exhibited 578 μmol/g/h production rate and 99% selectivity to HCOOH during liquid phase CO 2 hydrogenation owing to the unique amorphous alloy structure corresponding to the well-distributed, coordination-unsaturated, electron-enriched and synergistic active sites, which promoted the adsorption, activation, dissociation, and surface reaction of CO 2 and H 2. Moreover, the mesoporous channels also promoted the diffusion and adsorption of CO 2 and H 2. Besides, the Ru 1% CoB catalyst also displayed good durability in CO 2 hydrogenation owing to the robust stability against the crystallization of amorphous alloy, the collapse of mesopores, and the leaching of active sites. • Ordered mesoporous Ru(Co, Ni)B bimetallic amorphous alloy catalysts were synthesized. • The Ru 1% CoB displayed enhanced performance during CO 2 hydrogenation compared to nonporous and crystallized Ru 1% CoB. • The unique structure of amorphous alloy and mesoporous structure cooperated to promote the activity. [ABSTRACT FROM AUTHOR]

Accurate interdiffusion information is essential to control the phase transformation process in metastable β-type titanium alloys. In this work, diffusion behavior in the ternary Ti–Nb–Sn system at 1373 K and 1473 K was experimentally investigated. The ternary interdiffusion coefficients and impurity diffusion coefficients in the bcc Ti–Nb–Sn alloys were determined using the diffusion couple technique, along with the Whittle-Green and Hall methods. Based on the obtained diffusion coefficients, an atomic mobility database for the bcc Ti–Nb–Sn system was established via the CALPHAD (CALculation of PHAse Diagrams) method. In the optimizing procedure, the end members and the binary parameters for the bcc-Ti-Sn system were reassessed. The calculated results using the obtained database agree with the experimental diffusion properties (i.e., interdiffusion, composition-distance profiles and diffusion paths), demonstrating the accuracy of the database developed in this work. • The interdiffusion and impurity coefficients in bcc Ti–Nb–Sn were extracted via the Whittle-Green and Hall method. • The binary interaction parameters were optimized and reassessed for binary Ti–Sn system. • An atomic mobility database was established using CALPHAD method. • Simulation and calculations were processed and the results are consistent with the experimental data. [ABSTRACT FROM AUTHOR]

[Display omitted] • Four Fe-13Cr-4.5Al-2Mo alloys with different Nb content were designed. • In-situ electrochemistry was conducted to quantitatively verify corrosion behavior in 360 °C lithiated and borated water. • Slight Nb addition benefits corrosion resistance due to larger oxide impedance and delayed oxidation of Fe 2 Nb particles. • Cathodic Tafel kinetics of in-situ polarization curves reveals the oxygen reduction mechanism on FeCrAl surface. Niobium addition in candidate accident tolerant fuel (ATF) cladding FeCrAl alloy has received much attention, but its effect on high temperature water corrosion behavior has not been revealed. Four alloys with different Nb content (0 wt%, 0.5 wt%, 1.0 wt% and 1.5 wt%) based on Fe-13Cr-4.5Al-2Mo model alloy were designed, and the corrosion behavior was investigated by in-situ electrochemistry and microscopy. The in-situ electrochemistry analyses, including open circuit potential (OCP), polarization and electrochemical impedance spectrum, were carried out in 360 °C/19.0 MPa lithiated and borated water connected with a loop system to monitor the water chemistry. The oxide films formed after immersion for 85 days were deeply investigated by focused ion bombarding and transmission electron microscopy. Results have shown that OCP decreased with elevated temperature and corrosion potential increased with time. FeCrAl alloys have satisfactory corrosion resistance because of small corrosion currents and thin oxide films. Only monolayer multicrystal spinel oxide forms on FeCrAl alloys. Slight Nb addition (0.5 wt% and 1.0 wt%) benefits the corrosion resistance due to relatively large impedance of oxide and delayed oxidation of Fe 2 Nb particles. Porosities with Fe depletion were spotted in oxide and especially severe in 1.5 wt%-Nb alloy. Cathodic Tafel kinetics and corrosion mechanisms of FeCrAl were further discussed. [ABSTRACT FROM AUTHOR]

• Mn-Cu alloys are fabricated by laser powder bed fusion based on mixed element powders. • The optimal processing windows for the dense Mn-Cu alloys is discovered. • The as-fabricated Mn-Cu alloys present good tensile properties. Mn-Cu alloys with high Mn contents have good damping capacity but poor workability and mechanical properties. In this research, laser powder bed fusion (LPBF) was applied to fabricate the Mn-Cu alloys (Mn 63 Cu 37 , Mn 73 Cu 27 , and Mn 82 Cu 18) based on mixed element powders. The printability, microstructure and mechanical properties of the as-fabricated Mn-Cu alloys were investigated through a series of characterization methods. The results indicate that the Mn-Cu alloys with high relative densities (99.76–99.85%) can be fabricated using the optimal processing parameters. The as-fabricated Mn-Cu alloys show higher strengths (537.5–589.6 MPa) and yield strengths (404.0–440.1 MPa) than those of commercial Mn-Cu alloys fabricated by conventional methods. The tensile strength presents an overall downward trend with increasing Mn content. Thus, LPBF can be considered as a promising method to fabricate Mn-Cu alloys with high Mn contents. [ABSTRACT FROM AUTHOR]

Mo and Ta are two important β stable elements that can enhance the fatigue strength and reduce the elastic modulus of titanium alloy, and can significantly improve the biocompatibility of titanium alloy. It is significant to study the diffusion behavior in β Ti–Mo–Ta alloy for understanding the microstructure evolution in production process and developing new alloys. In this study, using several diffusion couples, the interdiffusion coefficients and impurity diffusion coefficients in β Ti–Mo–Ta alloy were extracted via Whittle-Green method and Hall method. The atomic mobilities in bcc phase in Ti–Mo–Ta system were obtained by assessing the experimental data using CALPHAD (CALculation of PHAse Diagrams) method. Simulations of the diffusion process in the diffusion couples were implemented using DICTRA Module in Thermo-Calc software. The calculated data were in good agreement with the experimental data, confirming the accuracy of the database. • The diffusion behaviors in bcc Ti–Mo–Ta alloys were studied at 1373 K and 1473 K. • The atomic mobilities in bcc Ti–Mo–Ta system were obtained using CALPHAD method. • Calculations and simulation were proceeded to examine the accuracy of the parameters. [ABSTRACT FROM AUTHOR]

In this study, a Mg-9Gd-4Y-2Zn-0.5Zr (wt.%) alloy was subjected, after solution treatment, to hot compression deformation at different temperatures (350 °C, 400 °C and 450 °C) and different strain rates (0.001 s−1, 0.01 s−1, 0.1 s−1 and 0.5 s−1) on a Gleeble-3800 thermal simulator. The evolution of the stress–strain curves under different conditions was compared. The changes in microstructure caused by the different deformation parameters and the change law of the long-period stacking-ordered (LPSO) phase during compression were observed and analyzed by optical microscope (OM) and scanning electron microscope (SEM). The results show that with the increase in the deformation temperature and the decrease in the strain rate, the degree of dynamic recrystallization (DRX) gradually increased, and the morphology of the phase also changed through, for example, twist fracture. The continuous dynamic recrystallization (CDRX) and discontinuous dynamic recrystallization (DDRX) mechanisms activated during the thermal deformation process can effectively refine the grains and weaken the texture in the alloy. [ABSTRACT FROM AUTHOR]

In this work, the extruded Mg-13Gd alloy sheet was fabricated by hot extrusion with small extrusion ratio of 3.9 (ER3.9) combined with the aging prior to extrusion (APE) treatment. The APE-ER3.9 and ER-3.9 samples show apparent heterogeneous lamella structure (HLS) and heterogeneous texture (HT), where fine dynamically recrystallized (DRXed) grains form a random texture and coarse un-DRXed grains exhibit a strong basal texture. Besides, amounts of pre-existing nano-precipitates are introduced in the APE-ER3.9 sample. The APE-ER3.9 sample exhibits the optimal combination of strength and ductility, which is attributed to the synergy of HT between coarse and fine grains, the elevated heterogeneous deformation-induced (HDI) strengthening and hardening, the pre-existing precipitates and the dynamic generation of nanoscale chain-like precipitates during deformation. The coarse grains mainly rely on the activation of basal and prismatic slips to maintain its work hardening. In fine grains, the basal slip dominates the whole deformation process, while the combined effects of activated pyramidal slip and cross slip play a significant role in accommodating the late deformation. This work provides a guide for designing Mg-RE alloys with excellent strength and ductility. [ABSTRACT FROM AUTHOR]

For the first time, a strategy to equalize the subunit volumes of [A 2 B 4 ] and [AB 5 ], and meanwhile increase the oxidation/corrosion resistance for superlattice hydrogen storage alloys is proposed. [Display omitted] • A novel sublattice modification strategy for supperlattice HSAs is proposed. • V [A2B4] and V [AB5] are equalized in a superlattice alloy for the first time. • Oxidation/corrosion resistance is enhanced by adding Gd with high electronegativity. • Cycling stability is significantly improved without losing capacity or HRD. Superlattice hydrogen storage alloys are one of the most potential candidates for the negative electrode materials of nickel-metal hydride batteries. However, their crystal structure damage and oxidation/corrosion during battery cycling severely deteriorate their cycle life. In this work, we propose a new strategy based on the alloys' structure characteristics analysis and First-principles calculation to enhance their cycling stability. The strategy equalizes the sublattice volumes of [A 2 B 4 ] and [AB 5 ] by atomic selective occupation and meanwhile increases the alloys' electronegativity. The feasibility of the strategy is validated experimentally by designing a series of single-phase superlattice alloys with simple elemental compositions of La 0.75- x Gd x Mg 0.25 Ni 3.5 (x = 0, 0.05, 0.1, 0.15). It is found that when appropriate amount of Gd is added, the sublattice volumes of [LaMgNi 4 ] and [LaNi 5 ] become equal, so that the alloy maintains a stable crystal structure in the long-term battery cycling. Moreover, the alloys' oxidation/corrosion resistance is enhanced due to the high electronegativity of Gd. The alloys' capacity retention after 100 cycles is improved from 82.1% (La 0.75 Mg 0.25 Ni 3.5) to 88.2% (La 0.60 Gd 0.15 Mg 0.25 Ni 3.5) without sacrificing the maximum discharge capacity, and meanwhile the high rate dischargeability is also increased. The design strategy provides new insights for overcoming the weakness in the cycling stability of superlattice hydrogen storage alloys, thus promoting their practical applications. [ABSTRACT FROM AUTHOR]

A 5 B 19 -type superlattice structure La–Mg–Ni-based alloys are potential anode material for nickel-metal hydride batteries due to outstanding durability and rate capability. However, the formation of multi-phase structures compromises cycling stability and poses the challenge in determining the specific effect of the element based on multiple components. Herein, we obtain Pr 5 Co 19 -type single-phase alloys and further study the effect of Mg element on structure and performance. It is found that the increased Mg strengthens the structure stability via reducing the volume mismatch between subunits and contributing to the weaken alloy pulverization. The optimized A 5 B 19 -type La 0.58 Sm 0.18 Y 0. 01 Mg 0. 23 Ni 3. 62 Al 0.16 alloy displays superior capacity durability with a capacity retention rate of 71.6% after 300 cycles, while that of La 0.58 Sm 0.21 Y 0. 01 Mg 0. 20 Ni 3. 62 Al 0.16 alloy is 68.1%. Besides, the increased Mg also optimizes the discharge performance at low temperature and high rate. The work aims to guide the design of composition and structure for hydrogen storage alloy with long period. • Pr 5 Co 19 La–Mg–Ni-based alloys with single phase are obtained. • Effect of Mg on structure and hydrogen storage properties of alloy is studied. • The increased Mg leads to enhanced subunit match and inhibited alloy pulverization. • The high Mg alloy delivers a high capacity retention rate of 71.6% after 300 cycles. • The increased Mg promotes the discharge performance at low temperature and high rate. [ABSTRACT FROM AUTHOR]

Rare-earth AB 5 -type alloys have great application potential in solid-state hydrogen storage. To further improve their plateau characteristics and cycling life, the effects of Fe on the long-term hydrogen storage properties of LaNi 5- x Fe x (x = 0, 0.5, 1) alloys are studied, and the function mechanisms are revealed. Fe induces a (Fe,Ni) phase layer with good ductility around LaNi 5 main phase, which plays a buffer role to relieve the microstrain during hydrogen absorption/desorption, thus stabilizing the crystal structure and improving the cycling performance. Further, Fe with larger atomic radius than Ni relieves the compression from 12 o to 6 m site of the LaNi 5 phase, and suppresses the plateau splitting phenomenon, resulting in a single and long hydrogen absorption/desorption plateau throughout 1000 cycles. This study promotes the understanding and application of cheap and effective Fe in improving the hydrogen storage properties of AB 5 -type alloys during long-term cycling. [Display omitted] • Long-term H 2 storage properties of LaNi 5- x Fe x alloys during 1000 cycles are studied. • (Fe,Ni) phase layer is induced by Fe addition. • (Fe,Ni) phase with good ductility decreases microstrain of H 2 absorption/desorption. • Fe addition relieves the stress of 6 m to 12 o sites, and suppresses plateau splitting. • Appropriate amount of Fe stabilizes crystal structure and increases capacity retention. [ABSTRACT FROM AUTHOR]

The recently emerged multicomponent (or medium/high entropy) alloys have generated considerable excitement globally in the last 10 years because of their excellent mechanical and functional properties, particularly in terms of strength-ductility combinations that can surpass most other metallic materials. However, the achieved high strength level (above 1 GPa in many cases) fuels strong concerns about hydrogen embrittlement (HE). Detailed investigation in this field is still scarce, especially pertaining to the face-centered cubic medium entropy alloys (MEA) that are typically strengthened by ordered precipitates. Here, we unravel the effect of γ' (L1 2) ordered precipitates on H-induced damage behavior and the associated HE resistance in CoCrNi-based MEAs. Compared with the equi-molar CoCrNi MEA, the precipitation-hardened (CoCrNi) 94 Al 3 Ti 3 MEA shows an enhanced HE resistance even at a higher strength level. Both alloys are fractured due to H-assisted intergranular cracking at the initial failure stage when loaded in the presence of H. The formation of intergranular cracks is primarily attributed to the H-induced decohesion at grain boundaries, where a high stress/strain concentration accompanied by a more intensive dislocation planar slip (or stacking fault formation) caused by H was observed. The presence of γ' precipitates serves to slow down the internal diffusion/migration of H due to the trapping effects. The precipitates with a relatively larger size (∼50 nm) also hinder dislocation planar slip thus decreasing the number of pile-up dislocations at grain boundaries. Both effects collectively reduce the tendency of H-induced intergranular cracking, leading to the improved HE resistance. The work reveals the positive role of ordered precipitates in H tolerance and thus provides some insights in further microstructure design of medium/high entropy alloys for applications in H-abundant environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Oxidation behavior of Al 8 Cr 13.3 Fe 63.5 Ni 11.2 Ti 4 complex concentrated alloy was studied in the air at 800 °C. Results show that the oxidation kinetics does not obey a parabola relationship. The oxidation process was divided into two distinct stages, transforming from an approximately parabolic law to a quasi-linear law at 10 h. This alloy exhibits excellent oxidation resistance with only 0.41 mg/cm2 of specific mass gain after 100 h oxidation, ascribed to the compact outer CrTi 2 O 5 +TiO 2 and inner Cr 2 O 3 +nano-scale CrTi 2 O 5 oxide layers. However, this oxide scale does not prevent the N from diffusion inward, forming the TiN and AlN in internal oxidation zone. • The Al 8 Cr 13.3 Fe 63.5 Ni 11.2 Ti 4 CCA exhibits promising oxidation resistance after 100 h of exposure to the air at 800 °C. • The oxidation kinetics of Al 8 Cr 13.3 Fe 63.5 Ni 11.2 Ti 4 CCA in the air at 800 °C do not obey a parabola relationship. • The outer CrTi 2 O 5 +few TiO 2 oxide layer and inner Cr 2 O 3 +nano-CrTi 2 O 5 oxide layer were formed after 100 h oxidation. • This oxide scale does not prevent the N from diffusion inward, forming the TiN and AlN in the deep internal oxidation zone. [ABSTRACT FROM AUTHOR]

Rare earth–Mg–Ni-based alloys with superlattice structures are novel anode materials for nickel metal hydride batteries, wherein A 5 B 19 -type alloys have been regarded as the replacement of the current commercialized A 2 B 7 -type alloys due to the superior discharge ability at high rates and cycling stability. However, it is still a challenge to further improve the hydrogen storage properties of the A 5 B 19 -type alloys in a low-cost approach. Herein, we select low-cost Mn and Fe elements to substitute Ni to further reduce the cost of an A 5 B 19 -type La 0.72 Y 0.13 Mg 0.15 Ni 3.70 Al 0.15 alloy and focus on their effects on the alloy's structure and hydrogen storage properties. Results show that the La 0.72 Y 0.13 Mg 0.15 Ni 3.65 Al 0.15 Fe 0.05 alloy features increased intrinsic gas-solid hydrogen storage ability of 1.44 wt% and hydrogen absorption enthalpy change of −22.9 kJ mol–1, which have been altered by 0.21 wt% and 7.3 kJ mol–1 in contrast to the La 0.72 Y 0.13 Mg 0.15 Ni 3.70 Al 0.15 alloy, respectively. Furthermore, the Fe substitution benefits capacity retention during electrochemical cycling compared to Mn, which maintains 87.5% and 62.4% after cycling 100 and 500 times. The Mn substitution results in superior rate capability compared to the alloy containing Fe. The work provides guidance for designing hydrogen storage alloys with superlattice structures to improve the electrochemical performance. • Pr 5 Co 19 -type alloys with low cost Mn and Fe substituted Ni are obtained. • Effect of Mn and Fe substituted Ni on hydrogen storage properties is clarified. • Fe substituted Ni increases hydrogen storage capacity from 1.23 wt% to 1.44 wt%. • Fe substitution rises the capacity retention from 52.6% to 62.4% at the 500th cycle. • Mn substitution optimizes the discharge ability at high rates. [ABSTRACT FROM AUTHOR]

The microstructural evolution and local mechanical properties of dendrites, including the fcc dendritic core (DC) and bcc/B2 inter-dendritic (ID) regions of Al 0.6 CoCrFeNi high entropy alloy (HEA) at different annealing temperatures were investigated by electron microscopy and nanoindentation tests. In the fcc DC region, nanoparticles of the ordered L1 2 phase precipitated at 600 and 700 °C. At 800 °C, the L1 2 phase was replaced by a fine needle-like ordered B2 phase, and B2 coarsened with increasing temperature. In the bcc/B2 ID region, as the annealing temperature increases, the disordered bcc gradually transforms to the σ phase, and the σ phase stably exists at 700 and 800 °C. The nanoindentation test results showed that the L1 2 , fine B2, and σ phases significantly increased the hardness of the DC and ID regions. In addition, the solidification paths of the as-cast alloy and the phase evolution mechanisms in the DC and ID regions were explored in conjunction with thermodynamic calculations. The investigation of the structural evolution and mechanical behavior of different microscopic regions will facilitate HEA design. • The L1 2 phase precipitates first in the fcc DC region of the Al 0.6 CoCrFeNi HEA and is replaced by the B2 phase at 800 °C. • σ phase precipitates only in the bcc/B2 ID region of the HEA. • The formation of dendritic as-cast Al 0.6 CoCrFeNi HEA was analyzed based on Scheil simulations. • The precipitation of L1 2 and B2 in the DC region was simulated by TC-PRISMA. • The phase evolution of the alloy was analyzed by thermodynamic calculations. [ABSTRACT FROM AUTHOR]

Rare-earth AB 5 -type alloys have been widely studied due to their great application potential in gaseous hydrogen storage, but their overall hydrogen storage properties still need to be further improved for more extensive applications. In this work, the effect of Sn partial substitution for Ni on the plateau characteristics and cycling performance of the LaNi 5- x Sn x (x = 0, 0.25, 0.5, 0.75, 1) alloys are systematically studied. It is found that the segregation effect caused by Sn addition leads to the multi-CaCu 5 phase structure with different cell parameters which may have a positive effect on stabilizing the alloys' structure during cycling by playing a buffer role. Also, the replacement of Sn element results in a higher anisotropic c/a value, which reduces microstrain and improves the cycle life. The capacity retention after 1000 cycles increases from 83.2% (x = 0) to 95.8% (x = 0.75). Moreover, the addition of Sn significantly reduces the hysteresis of the alloys from 0.212 (x = 0) to 0.023 (x = 0.5) at 383 K, owing to the reduction of the microstrain during hydrogen absorption/desorption. [Display omitted] • Hydrogen storage properties of LaNi 5- x Sn x alloys within 1000 cycles are studied. • Multiple CaCu 5 phases are induced by Sn addition. • Hysteresis is dramatically decreased by Sn addition. • Long-term cycling performance is significantly improved by Sn addition. • The novel result is the extension of the previously studied composition range. [ABSTRACT FROM AUTHOR]

[Display omitted] Realizing the simultaneous morphology and electrical conductivity tuning of non-noble metal nanocatalysts is urgently desired for promoting their intrinsic activity toward oxygen evolution reaction (OER), while it is still challenging. Herein, we have demonstrated that the morphology and conductivity of FeNi 3 alloy can be finely tailored via introducing the graphene carbon dots (GCDs). Benefitting from the enlarged active areas, significantly improved electrical conductivity, and strong synergistic coupling effect, the optimized FeNi 3 @GCDs-10 shows extraordinary electrocatalytic performance towards OER by delivering a current density of 10 mA cm−2 with the overpotential of 238 mV, as well as small Tafel slope of 48.7 mV dec-1. Density functional theory (DFT) calculations reveal that Fe is the dominated active sites for boosting water dissociation. In addition, the incorporation of GCDs can also strength the adsorption of *O and lower the energy barrier for the transformation from *OH to *O, thereby optimizing the free energy of *O and greatly promoting the OER activity. [ABSTRACT FROM AUTHOR]

• The oxidation behaviors of Zr-Sn-Nb and Zr-4 alloy were investigated under three ambients in the range of 650–1250 ℃. • The kinetics transitions for Zr-Sn-Nb and Zr-4 alloy under three test ambients were obtained and analyzed. • The break-away of oxide layer resulting from the martensite phase transformation of from t-ZrO 2 to m-ZrO 2 was clearly observed. • A multi-layer structure of oxide-nitride-oxide was found in air ambient caused by the re-oxidation of ZrN. • The effects of crack formation of oxide layer on oxidation resistance in various scenarios were studied. Zirconium-based alloys are widely used for fuel claddings particularly in pressurized water reactor. This study investigates the oxidation characteristics of Zr-4 and Zr-Sn-Nb alloy in steam, oxygen and air atmosphere respectively in temperature range of 650–1250 ℃ by a modified thermo-gravimetric analyzer. The oxidation rate exponents and oxidation kinetic correlations are calculated. The rate transitions of the kinetic oxidation for Zr-Sn-Nb and Zr-4 occur both at 1100 ℃ in steam, both 950 ℃ in air, and 1200 ℃ and 1150 ℃ in oxygen, respectively. The oxidation kinetics of both zirconium alloys in air is faster than in steam and oxygen. The maximum thickness of the oxide layers for both zirconium alloys is reached at 1150 ℃ in steam due to the phase transformation of the zirconium from monoclinic to tetragonal. The oxide layer formed in air is porous, heterogeneous with a multi-layer structure of oxide-nitride-oxide because of the formation and re-oxidation of zirconium nitride in oxygen starvation environment. The oxidation resistance of the zirconium alloy is related to the integrity and compactness of the oxide layer. Gas diffusion through the imperfection in the oxide scale may accelerate subsequent oxidation. [ABSTRACT FROM AUTHOR]

In this work, the microstructure and hydrogen storage properties of Ti 1- x Ce x V 0.45 Mn 1.5 (x = 0, 0.05, 0.10, 0.15, and 0.20) alloys have been studied. It shows that the x = 0 alloy consists of a C14 Laves single phase. Moreover, alloys containing Ce can exhibit the CeO 2 phase, whose content rises as Ce content does. Furthermore, CeO 2 phase aggregation causes the alloy to fracture and the hydrogen diffusion channel to enlarge. According to the PCT curves (25 °C), the plateau pressure increases with increasing Ce content, and the hydrogen storage capacity decreases with increasing Ce content due to increase in Ce content which does not absorb hydrogen. And it is also found that increase in Ce substitution for Ti results in better dynamic properties for the alloys. And the dehydrogenation kinetics curves show that hydrogen desorption rate substantially increases with x getting larger. This is because CeO 2 phase acts as the "hydrogen pump" to increase the rate of hydrogen discharge in the alloy, The fastest hydrogenation kinetics are shown, the best hydrogen storage performance is achieved, and the ma x imum hydrogenation is reached in less than 100 s. • According to the PCT curves, the plateau pressure increases with increasing Ce content and the hydrogen storage capacity decreases with increasing Ce content. • In this study, CeO 2 phase acts as the "hydrogen pump" to increase the rate of hydrogen discharge in the alloy. • CeO 2 phase aggregation leads to cracks in the alloy. [ABSTRACT FROM AUTHOR]

Cr 2 AlC diffusion barrier was prepared between NiCrAlY coating and TiAl alloy. Long-term cyclic oxidation was conducted at 900 °C in air for 1000 cycles(h). Cr 2 AlC and transformed Cr 7 C 3 , α-Cr and TiC had significant blocking effects on Ti diffusion. So, the Al-rich phase in the NiCrAlY coatings was NiAl rather than Ni 2 TiAl, which inhibited the generation of TiO 2 and avoided the presence of α-Cr in the Al 2 O 3 scales. As a result, the stability and spalling resistance of the Al 2 O 3 scales were enhanced. • Cr 2 AlC diffusion barrier for NiCrAlY coating on TiAl alloy effectively blocked Ti diffusion, so Al-rich phase in coating was β-NiAl rather than Ni 2 TiAl. • Cr 2 AlC, Cr 7 C 3 , TiC and α-Cr during annealing and oxidation blocked Ti diffusion. • Cr 2 AlC inhibited TiO 2 formation and avoided α-Cr in Al 2 O 3 scales. So, the stability and spalling resistance of the Al 2 O 3 scales were enhanced. [ABSTRACT FROM AUTHOR]

The 2195 Al-Cu-Li alloy is widely utilized in the aerospace industry due to its lightweight nature and high strength. Consequently, gaining a comprehensive understanding of techniques to enhance its microstructural and mechanical properties is crucial for the consistent production of reliable and high-strength aerospace components. In this investigation, a pristine 2195 industrial ingot was subject to three distinct forging pretreatments: PT1, which involved a direct three upsetting and three stretching (3U3S) process; PT2, which combined double stage homogenization (DH) with 3U3S; and PT3, which involved DH along with six upsetting and six stretching (6U6S). Subsequent warm deformation and T8 aging treatment were applied to the pretreated forgings. The microstructure evolution during the processes and the final mechanical properties in three orthogonal dimensions were examined. The findings revealed that the combination of DH and multi-dimensional forging (MDF) facilitated the dissolution of non-equilibrium phases to a greater extent. Consequently, the main strengthening phase transformed from the T 1 + δ' phase observed in PT1 to the denser T1 + little θ' phase observed in PT2 and PT3 after T8 aging treatment. Notably, the tensile strength and yield strength of PT2 and PT3 specimens increased by 20–30 MPa in all three directions. Moreover, the MDF process accelerated the recrystallization behavior from PT1 to PT3, resulting in a gradual reduction in the average grain size of the pretreated samples from 356 µm to 186 µm. Following warm forging and T8 aging, the grains exhibited a finer and equiaxed structure. Additionally, the coarse phase was identified as the primary source of transgranular cracking. The coarse phases within the matrix became more homogeneous and finer from PT1 to PT3, with a gradual decrease in their area fraction. On the fracture surfaces, the aggregation of coarse phases diminished. Consequently, the elongation in the z-direction improved, and the elongation anisotropy and standard deviation decreased in all three directions for PT3 specimens. The findings presented in this study provide valuable insights into the high-performance manufacturing of Al-Cu-Li alloys. • The DH and doubling the strain of MDF both promoted the dissolution of non-equilibrium phases. • Combine DH treatment with MDF enhanced the precipitation kinetics of the T 1 phase, increasing the strength by 20–30 MPa. • The coarse phase was the main transgranular cracking sources, which was diminished gradually by the improved process. [ABSTRACT FROM AUTHOR]

• Co+2 can accelerate the Co-Fe deposition, while Fe+2 can inhibit reduction of Co+2. • Co-Fe alloys with various Fe contents can be obtained from ethylene glycol system. • Co-Fe alloys presents a high catalytic activity for hydrogen evolution reaction. The co-deposition behavior of Co+2 and Fe+2 in ethylene glycol (EG) are investigated using cyclic voltammetry (CV) techniques. These results imply that Co+2 species can accelerate the Co-Fe co-deposition, while Fe+2 can inhibit the reduction of Co+2. Moreover, the two effects can be improved as Co+2 or Fe+2 concentration increases. Microstructural and compositional characteristics of the samples show that Co-Fe deposits with various Fe content can be obtained from anhydrous FeCl 2 and CoCl 2 in EG. Scanning electron microscopy imaging of the surfaces of these Co-Fe alloy coatings shows that they present a dense structure with spherical "nodules", the size of which is related to the Fe content. The electrocatalytic activity for hydrogen evolution reaction (HER) on the Co-Fe coatings is also investigated. These results indicate that its electrocatalytic activity can be improved as Fe contents increase from 2.2 to 9.8 wt.% and the Co-Fe alloy with 9.8 wt.% Fe exhibits the high electrocatalytic activity for HER with an overpotential of 124 mV at 10 mA cm−2 in 1 M KOH. [ABSTRACT FROM AUTHOR]

• The recent advancements in NORR on parameters, experimental systems, mechanism, and catalysts are summarized as a guidance for further investigations. • The NORR electrocatalysts are classified into metals and alloys, metal compounds, and non-metal materials to facilitate the understanding of various catalysts. • The strategies for improving the NORR activity are summerized to help the design of electrocatalysts for NORR. • The challenges and perspectives of NORR were proposed for future works. Fossil fuel combustion results in significant NO x emissions, which are harmful to the environment and human health. The reasonable and effective treatment of NO x pollution is an urgent requirement. The electrocatalytic reduction of nitric oxide (NORR) to ammonia is an emerging method that can convert the NO pollutant into an important industrial product under ambient conditions, exhibiting great advantages over the severe reaction conditions of selective catalytic reduction (SCR) and Haber-Bosch processes of NH 3 synthesis, therefore, attracting the great interest of researchers. In the last few years, lots of materials for NORR have been developed based on theoretical, computational, or experimental studies. However, further breakthroughs in the catalytic activity, selectivity, and Faraday efficiency of NORR electrocatalysts are required to address the limitations in practical applications. To help future research on NORR in both theoretical and experimental directions, we summarized the recent progress in the development of NORR electrocatalysts, classifying them into metals and alloys, metal compounds, and non-metal materials according to their nature. The mechanisms or reaction pathways of NORR are also discussed. Furthermore, the experimental parameters and devices for NORR are introduced to help with experimental studies in the future. The research directions and perspectives on the further development of NORR electrocatalysts are illustrated. This review summarizes the recent advancements in NORR on parameters, experimental, mechanism, and catalysts, illustrating the types of catalysts, and the strategies for improving activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Recent research has focused on the development of disk superalloys with better temperature capability and mechanical properties via a new alloying concept that uses high levels of Co and γ′ formers of Al, Ti, Ta and Nb to produce composite precipitation strengthening. In this work, alloying effects of Nb and Ta on phase stability, microstructure and property of a novel Ni-Co-based superalloy were systematically investigated using the high-throughput multi-component diffusion multiples (MCDMs) in combination with various high-throughput measurement tools. A deep learning-based image recognition method was developed to efficiently extract the γ′ morphological features, including area fraction, particle size, number density. The rapid characterizations of alloy compositions, microstructure and Vickers hardness (HV) enable us to establish the composition-dependent microstructural characteristics and mechanical property as well as their correlation with the phase stability, which can be directly applied for designing Ni-Co-based superalloys with superior microstructure stability and strength. [Display omitted] [ABSTRACT FROM AUTHOR]

The 2195 Al-Cu-Li alloy is widely utilized for the fabrication of key aerospace vehicle components; hence, an in-depth understanding of its hot deformation behavior is essential for consistently achieving high-performance products. In this study, isothermal compression tests were performed on 2195 Al-Cu-Li alloy ingots in the temperature and strain rate ranges of 250–500 °C and 10−3-1 s−1, respectively. A processing map was established to predict the workability under different conditions. The corresponding microstructures were examined to reveal their hot deformation mechanism. Results demonstrated that the processing map was divided into four distinct domains. The unstable zone was located in the 250–375 °C/10−1.5-1 s−1 and 250–275 °C/10−2.5–10−1.5 s−1, temperature/strain rate regimes, in which deformation bands and flow localization were observed. The deformation bands blocked dislocations and compromised the dynamic recrystallization (DRX) behavior, hence damaging the microstructure. Further, large coarse T 1 phases precipitated in the 325–410 °C/10−2.5–10−3 s−1 regime, which led to the formation of heterogeneities in the microstructure, corresponding to a minimum workability in the processing map. The optimal hot-working domain for the 2195 alloy was determined to be 460–500 °C/10−3–10−2 s−1, and the dominating hot deformation mechanisms were DRX and dynamic recovery (DRV). Specifically, continuous and discontinuous DRX behaviors dominated in the 300–400 °C/10−3 s−1 and 450–500 °C/10−3 s−1 regimes, respectively. DRX gradually weakened as the strain rate increased at 500 °C. Further, the weakening of DRX was only minimally affected by temperature at 400–500 °C during high-speed deformation (1 s−1). The results reported herein can provide valuable insights into the hot working of Al-Cu–Li alloys. • A processing map (PM) was established to accurately predict the hot deformation behavior of the 2195 alloy. • Deformation bands and flow localization were the main microstructure response in the unstable domain. • Large coarse T 1 phases precipitated in the precipitation sensitive domain, leading to heterogeneity deformation. • The optimal hot working domain was 460–500 °C/10−3–10−2 s−1, which was dominated by DRX and DRV. • Within the 300–400 °C/10−3 s−1 regime, CDRX was the main DRX mechanism, whereas DDRX predominant at 450–500 °C/10−3 s−1. [ABSTRACT FROM AUTHOR]

Knowledge associated with the alloying effects of Al, Ti, Ta and Nb on phase stability of Ni-Co-based superalloys plays a significant role in efficiently exploring the multi-component space for future alloy designs, and thus were systematically investigated using a high-throughput dual-anneal multi-component diffusion multiple (MCDM) approach. In this work, η phase presenting considerably different morphology and spatial distribution was confirmed in the Ta-rich and Nb-rich alloys, and its zero-phase-fraction (ZPF) line at 800 °C was determined that suggests a maximum Nb + Ta content of about 2.5 at.% while avoiding the η formation. The composition criterion regarding the stability of η was updated by taking into account the destabilizing effect of Co such that the η formation can be significantly suppressed with increasing Co from a critical level of about 12 at.%, providing essential guidance to design alloy chemistry for superior microstructural stability at high-temperature service conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, the effect of heat treatment (760–1060 °C) on tribological behavior of selective laser melted Ti6Al4V alloy against Si 3 N 4 counter-ball under different applied loads was investigated. Results show the wear rate of as-built Ti6Al4V alloy increased firstly and then gradually decreased with increasing the heat-treatment temperature, which obtained the lowest value when the heat treatment temperature was 1060 °C, exhibiting the best wear resistance. The higher applied load led to larger wear rate and lower coefficient of friction. The wear mechanism was strongly dependent on the microstructure transformation, micro-hardness and applied load, which was discussed in detail. • Ti–6Al–4V alloys were fabricated by selective laser melting. • Friction coefficient and wear resistance were optimized by heat treatment. • Higher applied load led to larger wear rate and lower friction coefficient. • Wear mechanism was strongly dependent on the microstructure transformation, micro-hardness and applied load. [ABSTRACT FROM AUTHOR]