Phase Properties Research Articles

FeSiBCCr bulk metallic glasses with excellent soft magnetic properties prepared using spark plasma sintering technology

Fe-based amorphous alloys have received much attention in the fields of electronics and electrical due to their excellent soft magnetic properties at high frequency. However, the controllable preparation of large-sized Fe-based bulk metallic glasses (BMGs) still faces numerous challenges. In this study, FeSiBCCr amorphous powders prepared by gas-water combined atomization were used as raw materials, and FeSiBCCr BMGs were prepared through spark plasma sintering (SPS) at different pressures. The microstructure, phase and magnetic properties of the compacts were systematically characterized using SEM, XRD, TEM, DSC, and VSM. The results showed that when the sintering pressure was 50 MPa, the slow densification process dominated by particle rearrangement at the initial densification process made the internal contact resistance of the compacts larger. This led to macroscopic inhomogeneous physical fields and severe local overheating during the later stages of sintering, causing the precipitation of α-(Fe, Si) and Fe3B phases. Although the material exhibited a relatively high saturation magnetization (Bs) of 1.08 ± 0.01 T, the low density and amorphous fraction resulted in a high coercivity (Hc) of 1060.8 ± 37.8 A·m-1. When the sintering pressure was increased to 250 MPa, the degree of particle densification significantly improved, and the temperature inhomogeneity was markedly suppressed due to reduced internal resistance. Thus, the prepared FeSiBCCr BMGs exhibited an extremely high density of 6.66 ± 0.06 g·cm-3 and excellent soft magnetic properties with Bs of 1.23 ± 0.01 T and Hc of 18.8 ± 1.8 A·m-1. This indicated that the FeSiBCCr BMGs prepared in this study exhibited broad application prospects in efficient electromagnetic conversion and advanced electronic devices.

Effect of Al2O3 on the sintering process and the metallurgical performance of sinter

ABSTRACT The trend to process iron ore with increasing Al2O3 content has affected the performance of sinter and blast furnace operations. Formation of the primary melts and phase properties such as morphology and reducibility of the iron ore could be easily influenced by the Al2O3 content. In this paper, the effect of the Al2O3 content in the sinter samples, which range from 1.49 to 3.24 wt-% with a basicity of 2.0, MgO/Al2O3 ratio of 1.05, on the sintering process and the metallurgical performance were studied through a sinter pot experiment and a reduction experiment. The results show that an increase in the Al2O3 content deteriorated the sintering index, and the yield and tumble index decreased by 7.61% and 12.02%, respectively. The sintering index was relatively stable when the Al2O3 content was between 2.10 and 2.95 wt-%. Low-reduction columnar silico-ferrite of calcium and aluminum increased with the increasing Al2O3 content, hindered the reduction index of the sinter. The low-temperature reduction degradation index change was only around 2%, due to the higher MgO content of the sinter promoting magnetite formation.

Sintering, microstructure and mechanical properties of anorthite-based ceramics prepared from iron-extracted steel slag

Steel slag is a promising source of ceramic materials, but it causes a waste of iron resources and inferior ceramic performance because the slag contains over 30 % iron oxides. To deal with this problem, we proposed a two-step utilization process for steel slag, including iron extraction by smelting reduction and ceramics preparation from residual slag. In this work, the effect of the reduced slag addition on phase constituents, microstructure, and properties of this novel ceramic was studied. The major crystalline phase is anorthite for all the ceramics. Although abundant liquid is expected theoretically in conventional ceramics at 1175 °C, it did not achieve vitrification until 1250 °C. The slag addition plays different roles in sintering under various slag contents. After introducing 15 wt% slag, the sintering and pore elimination are accelerated significantly because of the slag’s fluxing effect although the ceramic shows no change in the theoretical liquid content. The ceramics have no advantage in producing liquids with further increasing the slag content. Therefore, limited densification is observed with 30 wt% slag addition owing to the lack of liquid phase. Fortunately, solid solution diopside is largely generated in the anorthite matrix with 45 wt% slag addition, greatly enhancing the ion diffusion and grain growth. This effect contributes to a highly dense and uniform sintered structure with small rounded pores at 1175 °C, at which its flexural strength increases by 92 % compared to the conventional ones. However, a higher slag addition in the ceramic should be avoided to ensure satisfactory structure integrity.

Pre-stimulus EEG phase coherence predicts visual target detection failures in schizophrenia: A pilot study

Impaired visual target detection is a common finding in schizophrenia that is linked to poor functional outcomes. However, the neural mechanisms that contribute to this deficit remain unclear. Recent research in healthy samples has identified relationships between the phase of pre-stimulus electroencephalographic (EEG) activity in the alpha band (8-12 Hz) or theta band (4-7 Hz) and the likelihood of visual target detection with and without attentional cueing, but these effects have not yet been explored in schizophrenia. We performed a study to investigate such effects in schizophrenia (n = 19) and healthy participants (n = 14), using a visual target detection task with attentional cues. We found significant relationships between pre-stimulus EEG phase properties and visual target detection in both groups, but also clear differences in the effects as a function of frequency, group, and attentional cueing. Alpha-band phase effects were relatively uniform across groups and conditions. By contrast, theta-band phase effects showed differences by group and attentional condition which could be consistent with attentional hyperfocusing in the schizophrenia group. Thus, our results elucidate a novel neural mechanism that may help to explain known impairments affecting both visual target detection and attention in schizophrenia.

Prediction of phase and tensile properties of selective laser melting manufactured high entropy alloys by machine learning

Selective laser melting (SLM) for high entropy alloys (HEAs) holds significant promise in commercial applications, and substantial experimental research efforts have been directed toward this domain. To take advantage of the reported experimental data of SLM manufactured (SLM-ed) HEAs and reduce unnecessary experimentation, this study incorporates machine learning (ML) techniques for the phase and tensile properties prediction of SLM-ed HEAs, thus presenting a novel avenue for accelerating the discovery of new SLM-ed HEAs. Through the adjustment of material descriptors and ML models, a model has been developed with an impressive accuracy of 81.58 % in distinguishing between face-centered cubic (FCC), body-centered cubic (BCC), and dual-phase (FCC+BCC) of SLM-ed HEAs. Additionally, optimized models have been devised for the prediction of tensile properties of SLM-ed HEAs, namely ultimate tensile strength (UTS) and yield strength (YS), achieving noteworthy MAPEs (mean absolute percentage errors) of 20.43 % and 20.25 %, respectively. Furthermore, several HEAs were fabricated using SLM, and the experimental outcomes exhibited a favorable alignment with the predicted results. These efforts carry significant implications in advancing the utilization of SLM for HEAs.

Phase evolution, microstructure and properties of glass-ceramics derived from municipal solid waste incineration bottom ash and molybdenum tailings

Municipal solid waste (MSW) incineration bottom ash (BA) and molybdenum tailings (MTs) are bulk solid wastes that have low added value and is of a serious environmental concern. Hence, it is imperative to develop technology that potentially as convert these wastes into potential products that are safe to handle. In the present work, the goal is to synthesize glass-ceramics from BA and MTs without addition other supplement materials. The study attempts to assess the influences of raw material ratio and sintering temperature on the phase transformation, microstructure and properties of glass-ceramics. The synthesized product shows that diopside ferroan and anorthite were the dominant crystals, and the content of diopside ferroan and anorthite increased with an increase in the proportion of MTs. It was observed that the presence of Fe2O3 and TiO2 inside solid wastes promote nucleation facilitating growth of crystals. Diopside ferroan and anorthite distribute uniformly and are well interweaved, densifying the structure with favorable properties of glass-ceramics. At the optimal processing temperature the presence of Na2O and K2O in the raw materials act as fluxing agents that facilitate formation of liquid phase, that enhance diffusion and rate of crystallization. The optimal mass ratio of BA to MTs was 45:55 and the sintering temperature of 1000 °C, exhibited the best comprehensive properties of the glass ceramics. At the optimal conditions the flexural strength, Vickers hardness, bulk density and water absorption were observed to be 76.00 MPa, 5.77 GPa, 2.69 g/cm3 and 0.32 %, respectively. The leaching test proved stability of the glass ceramics, and hence can serve to be a potential way of utilizing the waste into a valuable product benefiting the environment and promoting sustainable growth.

Effect of anionic groups in zwitterionic hydrophilic stationary phases on their chromatographic characteristics

The structure of zwitterion has great impact on the separation properties of zwitterionic hydrophilic stationary phases. To better understand the role of anionic groups of zwitterions, a novel carboxybetaine-based zwitterionic monolithic column was first prepared through thermo-initiated copolymerization of functional monomer (3-acrylamidopropyl)-dimethyl-(2-carboxymethyl) ammonium (CBAA) and crosslinker ethylene dimethacrylate (EDMA) within 100 μm ID capillary. The optimal poly(CBAA-co-EDMA) monolithic column exhibited satisfactory mechanical and chemical stability, good repeatability, high column efficiency (96,000 plates/m), and excellent separation performance for different classes of polar compounds (i.e., phenols, monophosphate nucleotides, urea and allantoin). A comparative study was then performed among three zwitterionic hydrophilic stationary phases containing different anionic groups, i.e. poly(CBAA-co-EDMA) (carboxybetaine), poly(2-{2-(methacryloyloxy) ethyldimethylammonium}ethyl n-butyl phosphate-co-EDMA) (phosphocholine), and poly(N,N-dimethyl-N-(3-methacrylamidopropyl)-N-(3-sulfopropyl) ammonium betaine-co-EDMA) (sulfobetaine) using benzoic acid derivatives, amine compounds, nucleobases and nucleosides as model analytes. The carboxybetaine-based monolithic column exhibited much higher positive zeta-potential and hydrophilicity, which endows it with a stronger retention capacity for acidic and neutral compounds, but sulfobetaine-based monolithic column exhibited much higher selectivity and retention capacity for the amines. Moreover, their enrichment efficiencies for N-glycopeptides were also evaluated based on their different hydrophilicity, and it was observed that the poly(CBAA-co-EDMA) monolithic material captured 4-8 times more N-glycopeptides compared to the other two materials.

Study on the high-strength and high-conductivity modification mechanisms of C7035 copper alloy induced by La and Sc doping

The effects of multi-element doping on mechanical and electrical properties of C7035 copper alloy were investigated by first principles calculation and experiment based on density functional theory (DFT). The results show that the addition of lanthanum (La) significantly improves the electrical conductivity of copper alloy, mainly because the precipitated phase of lanthanum (La) has high electrical conductivity, and promotes the formation of high-density twins in 0 Cu matrix. The electrical conductivity of the C7035 alloy doped with La reaches 80.19 % of IACS, which is 44.17 % higher than that of the alloy without La. In addition, the incorporation of scandium (Sc) increased the yield strength of the alloy to 635.63 MPa, an improvement of 25.65 %, due to the excellent mechanical properties of the ScCu₄ precipitated phase. The highly conductive NiSi precipitated phase is formed by the copper alloy doped with La and Sc simultaneously. Compared with the undoped alloy, the yield strength and conductivity of the co-doped alloy are 672.27 MPa, 62.7 %, 32.89 % and 12.73 % respectively. In summary, the coupling doping of La and Sc improves the mechanical and electrical properties of C7035 copper alloy, which provides theoretical guidance for the design of high-strength and high-conductivity copper alloys.

Surface Modification of Chromium–Nickel Steel by Electrolytic Plasma Nitriding Method

Electrolytic plasma nitriding is an attractive chemical heat treatment used to improve the surface properties of steel by implementing nitrogen saturation. This method is widely applied to steel and iron-based alloys operating under various operating conditions. In this work, using liquid-phase plasma nitriding technology, a nitrided layer was obtained on the surface of 40CrNi steel in electrolytes of different concentrations. The microstructure and phase composition of the nitrided layer were investigated and analyzed using scanning electron microscopy (SEM) and X-ray diffraction (XRD), and we performed Vickers hardness and wear resistance tests using the ball-on-disc method. The microhardness and wear resistance of nitrided 40CrNi steel were significantly improved due to the lubricating properties of the ε-Fe2N phase formed on its surface.

Multiscale fatigue life prediction model for CFRP laminates considering the mechanical degradation of its constituents and the local stress concentration of the matrix

In the present research, a novel approach for predicting the fatigue life of composites is proposed using a multiscale fatigue model. This model considers two critical physical phenomena that occur in CFRP laminates under tension-tension cyclic loading – the degradation of the physical properties of CFRP constituents and the localized stress concentrations within the matrix. To achieve this, Mori-Tanaka’s mean field theory, a well-known micromechanics model, is employed to consider the deterioration of material properties in various phases, which is dependent on the applied stress level. Localized stress concentration phenomena within the matrix of a composite material are common when CFRP laminate is subjected to cyclic loading. The localized stress concentration on a matrix with different numbers of fibers and orientations using representative volume elements (RVE) is investigated. Two other scales of failure criteria are defined to evaluate its constituent at the material level and ply level at the macroscale. A comparison with fatigue experiment data of AS4/3501-6 composite shows good reliability of the proposed multiscale fatigue model.

Twist elastic constant of chiral nematic cellulose nanocrystals determined by tactoid reconfiguration in electric field

Lyotropic chiral nematic cellulose nanocrystals (CNCs) have attracted significant attention and great progress has been made. Investigating their physical parameters, especially the twist elastic constant (K22), is pivotal for advancing our comprehension of fundamental viscoelastic property of chiral nematic phase. In this study, we demonstrate a straightforward method to simultaneously estimate K22 and helical twisting power (Kt) of chiral nematic CNCs. This method involves analyzing rheology properties and electro-response of CNCs, focusing on the rotational dynamics and structural reconfiguration of CNC tactoids under an electric field. By examining the rotation dynamics of CNC tactoids under an electric field, together with the viscosity characterization, the anisotropic dielectric susceptibility (∆χ) of chiral nematic CNC along the helix axis was determined. Subsequently, K22/∆χn was extracted by analyzing CNC tactoid pitch evolution under an electric field, employing the de Gennes model. The K22 for different concentrated CNCs is finally estimated by integrating experimental results and theory. It is shown that the chiral nematic CNCs present concentration-dependent K22, ranging from 0.05 to 0.14 pN, while Kt spans from 0.06 to 0.14 pN/μm. This study offers a comprehensive understanding of the CNC fundamental viscoelastic property and opens up new avenues for K22 measurement in other lyotropic liquid crystals.

Effects of spatial microstructure characteristics on mechanical properties of dual phase steel by inverse analysis and machine learning approach

This work aims to investigate complex relationship between microstructure characteristics and mechanical properties of dual phase (DP) steel through an inverse analysis based on Markov chain Monte Carlo (MCMC) method combined with meso-scale material modelling. In this framework, a machine learning approach as surrogate model was developed, in which support vector regression (SVR) and artificial neural network (ANN) were trained using results from representative volume element (RVE) simulations coupled with damage model, which were previously calibrated with experimental data of commercial DP steel grades. Moreover, specific microstructure descriptors including Moran’s index, martensite band index and martensite orientation were proposed for representing effects of spatial distributions of martensitic phase. As a result, inverse predictions of microstructure characteristics of DP steels for achieving defined yield strength, tensile strength, uniform elongation and toughness were presented. The inverse analysis could solve the non-uniqueness of structure–property relationships of steel, whereby significances of dispersed structures and aligned martensite bands were highlighted in details. The approach fairly dealt with multi-target optimization and high dimensional problem, which can be further applied as a guideline for designing DP microstructures with enhanced mechanical properties.

Hydrothermal carbonization of combined food waste: A critical evaluation of emergent products

Hydrothermal carbonization (HTC) increasingly appears as an eco-friendly method for managing food waste (FW). In this work, a combination of FW was subjected to HTC, and products were critically evaluated. This involved a lab-scale pressure reactor and optimization of HTC conditions: temperature (220–340 °C) and residence time (90–260 min) via central composite design type of response surface methodology (CCD-RSM). Results showed varying temperatures and residence time to impact the hydrochar (HC) and hydrothermal carbonization aqueous phase (HTC-AP) properties. Although HC produced through HTC exhibited lower ash content (<2%) despite higher fixed carbon (>55 %) with respect to the raw FW, the heating value of HC ranged from 19.2 to 32.5 MJ/kg. Temperature primarily influenced FW conversion, affecting carbonaceous properties. Saturated fatty acids (SFA) were found to be predominant in the HTC-AP under all tested operating conditions (77.3, 48.4, and 37.1 wt% for HTC at 340, 280, and 220 °C in 180 min, respectively). Total phosphorus recovery in HC and HTC-AP respectively peaked at 340 °C and 220 °C in 180 min. The study concludes that HTC holds promise for energy-dense biofuel production, nutrient recovery, and fostering a circular economy.

Efficient hydrogen production performance of 1T-2H MoSe2/ MnxCd1-xS Z-type heterojunction photocatalysts under visible light

Finding suitable co-catalysts to help metal sulfides achieve effective bulk phase and surface charge separation is the key to improving their photocatalytic performance. In this paper, two-phase 1T-2H MoSe2 was loaded onto the surface of Mn0.4Cd0.6S solid solution with a twin crystal structure, and the 1T-2H MoSe2/Mn0.4Cd0.6S Z-type heterojunction structure was successfully constructed to realize the high efficiency of hydrogen production in the visible light. The metallic properties of the 1T phase can significantly improve the catalytic activity of MoSe2. The transition from the 2H to the 1T phase can lead to the creation of extra defects, such as unsaturated Mo and Se, thereby increasing the number of active sites on the photocatalyst surface. The two crystalline phases are staggered and form homogeneous junctions within them in the twin crystalline structure Mn0.4Cd0.6S prepared under an alkaline environment, which gives it excellent bulk and charge separation properties. After loading, the 1T phase MoSe2 at the interface of MoSe2 and Mn0.4Cd0.6S can accelerate the charge separation between the interfaces, and the Z-type heterojunctions formed by the two and the better retention of useful excitation electrons and holes. The 1% 1T-2H MoSe2/Mn0.4Cd0.6S could achieve a notable hydrogen production rate of 12.34 mmol ∙ g−1∙ h−1, surpassing that of the Mn0.4Cd0.6S solid solution. This non-precious metal-loaded homojunction photocatalyst effectively harnesses solar energy to produce clean H2 under mild conditions, giving a promising prospect for practical applications and laying the groundwork for further exploration of MnxCd1-xS photocatalysts.

Study on the effects caused by defect LaK in KH2PO4 crystal

Based on first-principles calculations, we have investigated the effects of different charged states of LaK on the defect formation energies (DFE), lattice distortions, electronic structures, and optical properties of paraelectric phase (PE-KDP) and ferroelectrical phase (FE-KDP) crystals. Our calculations indicate that LaK·· is readily formed in both crystal structures, and the degree of H–O bond distortion is more pronounced in PE-KDP. This could explain the formation of small growth mounds on the surface of La-doped crystals observed in the experiments, as well as the large decrease in the hardness of La-doped crystals. Furthermore, the band gap value of La-doped crystals is smaller than that of perfect crystals. This can be attributed to the fact that the 5d orbitals of La affect the 2p orbitals of O located in the conduction band minimum (CBM), resulting in a splitting of the energy levels and the formation of a defective energy level that enters the forbidden band. The optical spectra have been obtained considering the electron-phonon coupling. Large stokes redshift and nonradiative jump will lower the crystal laser damage threshold. The La-doped PE-KDP has an absorption band at 3.03 eV (409 nm) in good agreement with the experimentally observed absorption band at 390 nm.

MIL-125 (Ti) and porous dielectric polymer substrate introducing composite gel polymer electrolyte with enhanced mechanical property, thermal stability and electrochemical property

Lithium metal batteries have potentially high energy density, but severe uncontrolled lithium dendrites and unstable side reactions prevent large-scale applications. Serial three-dimensional porous poly (vinylidene fluoride) and copolymer membrane-based composite gel electrolytes are designed by introducing MIL-125 (Ti) and ethylene carbonate. Abundant lithium-ion transportation channels and homogeneous ion transport microregion are provided the new type porous fluoropolymer substrate. We also find that crystalline phase and dielectric properties of serial polymer membrane have significant impact on electrochemical performance for composite gel electrolytes. The mechanical and dielectric property of composite electrolyte enhanced by incorporating uniform and well distribution MIL-125 (Ti), which improve the electrolyte/electrode interface charge distribution and promote uniform lithium deposition, leading to lithium dendrite suppression. MIL-125 (Ti)/P(VDF-TrFE-CTFE) composite membrane shows the enhanced maximum strain of 181 %, thermal stability (188 °C) and corresponding composite gel electrolyte reflects higher ionic conductivity of 1.7 × 10–3 S cm-1 and wider electrochemical window at room temperature than PVDF and PVDF-HFP composite electrolytes. Expectedly, quasi-solid state lithium metal battery of MIL-125 (Ti)/P(VDF-TrFE-CTFE) composite gel electrolyte exhibits higher discharge capacity (152.8 mAh g-1) at 240th cycle and 1 C, longer cycling life and better rate performance under large current density than PVDF and PVDF-HFP composite electrolytes.

Optimizing heat transfer with electro-osmotic ciliated propulsion in a non-uniform canals with Cu-blood characteristics considering thermal casson nano fluid

Electroosmosis peristaltic flows find promising applications in electro-fluid thrusters in space propulsion, polymer injection systems, ion exchange membrane designs, microbe fuel cells, biochip fabrication and fossil fuel energy process. In light of this, the current work aims to investigate blood based electroosmotic peristaltic flow in a ciliated, non-uniform propagation channel when copper nanoparticles are present. For that purpose, mathematical modeling is done in two dimensional frame and then governing partial differential equations are simplified and converted in ordinary differential equations using dimensionless quantities and long wave length and low Reynolds number approximations. In result we got coupled nonlinear boundary value problem that is solved numerically using three-stage Lobatto IIIa formula known as bvp4c invoking shooting technique. Peristaltic ciliated waves are thought to pass along the channel wall. The properties of both fluid phase and particle phase flow are modeled and investigated. Plotting against various parameters, streamline contours, temperature contours, concentration and temperature profiles, and pressure rise graphs are examined in-depth from a physical perspective. The obtained results revealed that concentration profile α upsurges for rising values of Casson fluid parameter β, nanoparticle volume fraction ϕ and flow rate Q while it drops with an increase in particulate volumetric fraction C, Eckert number Ec, Soret number Sr, Schmidt number Sc and viscosity constant. A decrease in temperature is also caused by an increase in the volumetric percentage of nanoparticles. In the pumping portion, there is a decrease in pressure rise; however, this decrease changes to an increase in the increased pumping zone.

Effect of rare earth elements scandium on Sn-0.7Cu brazing metal: First-principles calculation

In this paper, the effects of rare earth element Sc on the thermal and mechanical properties of precipitates (Cu6Sn5), (Cu3Sn) and Sn matrix in Sn-0.7Cu brazing metal, as well as the interface bonding strength between stable precipitates (Cu6Sn5) and Sn matrix were investigated based on first-principles calculations. The results show that the electronic structure of the precipitated phase and the matrix changes to a certain extent, the atomic bonding mode recombines, and the electron orbitals of the matrix atoms and the rare earth elements hybridize. In addition, rare earth elements improve the mechanical properties of precipitated phase and matrix, increase the plasticity of precipitated phase and enhance the strength of matrix. Rare-earth elements improve the thermodynamic properties of the matrix and precipitated phase to some extent, increase the heat capacity of the precipitated phase and the matrix, and reduce the melting point. At the same time, rare earth elements enhance the mechanical properties and thermodynamic stability of the interface between the precipitated phase and the matrix, and improve the oxidation resistance of the matrix. Transmission electron microscope (TEM) observation shows that there is a segregation of Cu atoms at the interface between precipitated phase and matrix. Other experimental results show that: Rare-earth element Sc has a positive effect on the mechanical properties, melting characteristics and oxidation resistance of the filler metal alloy. When the addition of Sc is 0.1 % (wt), the tensile strength and elongation of the alloy are significantly increased, the melting point is reduced, the surface oxidation resistance is increased, and the comprehensive properties of the alloy are the best.

Untangling individual cation roles in rock salt high-entropy oxides

We unravel the distinct role each cation plays in phase evolution, stability, and properties within the Mg1/5Co1/5Ni1/5Cu1/5Zn1/5O high-entropy oxide (HEO) by integrating experimental findings, thermodynamic analyses, and first-principles predictions. Our approach is through sequentially removing one cation at a time from the five-component high-entropy oxide to create five four-component derivatives. Bulk synthesis experiments indicate that Mg, Ni, and Co act as rock salt phase stabilizers whereas only Mg and Ni enthalpically enhance single-phase rock salt stability in thin film growth; synthesis conditions dictate whether Co is a rock salt phase stabilizer or destabilizer. By examining the competing phases and oxidation state preferences using pseudo-binary phase diagrams and first-principles calculations, we resolve the stability differences between bulk and thin film for all compositions. We systematically explore HEO macroscopic property sensitivity to cation selection employing both predicted and measured optical spectra. This study establishes a framework for understanding high-entropy oxide synthesizability and properties on a per-cation basis that is broadly applicable to tailoring functional property design in other high-entropy materials.

Achieving the Superior Abrasive Wear Resistance in ZTAP/Fe Composites from the Theoretical Calculations Guided Designing of Metallurgical Interface Transition Layer

Using the first-principles calculations and phonon QHA method, the thermodynamic stability, mechanical and thermophysical properties of binary Ni-Ti phases are obtained. The most thermodynamically feasible binary Ni3Ti phase with a superior elasticity and mechanical tensile strength is designed as the interfacial transition layer between ZTA ceramic particles and iron matrix. A high-Cr white cast iron matrix composite reinforced with ZTA particles is fabricated via infiltration casting process. The microstructures and three-body abrasive wear resistance of the composite are investigated. The obtained ZTAP/Fe composite has a compact metallic Ni3Ti metallurgical transition layer with a small amount of AlNi2Ti and TiO phases in the interfacial region, leading to a strongly adhesion between iron matrix and ZTA ceramic particles due to the presence of covalent Ti-O, Fe-O and Zr-O bonds. The composite exhibits the relative wear resistance 12.9 times higher than that of reference Cr15 specimen. The wear mechanism of the ZTAP/Fe composite is mainly attributed to the removal of iron matrix under the SiO2 abrasives, as revealed from the secondary electron images and laser scanning confocal topography.