Interfacial Behavior Research Articles

From Antagonism to Enhancement: Triton X-100 Surfactant Affects Phenanthrene Interfacial Biodegradation by Mycobacteria through a Shift in Uptake Mechanisms.

Polycyclic aromatic hydrocarbons (PAHs), as persistent environmental pollutants, often reside in nonaqueous-phase liquids (NAPLs). Mycobacterium sp. WY10, boasting highly hydrophobic surfaces, can adsorb to the oil-water interface, stabilizing the Pickering emulsion and directly accessing PAHs for biodegradation. We investigated the impact of Triton X-100 (TX100) on this interfacial uptake of phenanthrene (PHE) by Mycobacteria, using n-tetradecane (TET) and bis-(2-ethylhexyl) phthalate (DEHP) as NAPLs. Interfacial tension, phase behavior, and emulsion stability studies, alongside confocal laser scanning microscopy and electron microscope observations, unveiled the intricate interplay. In surfactant-free systems, Mycobacteria formed stable W/O Pickering emulsions, directly degrading PHE within the NAPLs because of their intimate contact. Introducing low-dose TX100 disrupted this relationship. Preferentially binding to the cells, the surfactant drastically increased the cell hydrophobicity, triggering desorption from the interface and phase separation. Consequently, PAH degradation plummeted due to hindered NAPL access. Higher TX100 concentrations flipped the script, creating surfactant-stabilized O/W emulsions devoid of interfacial cells. Surprisingly, PAH degradation remained efficient. This paradox can be attributed to NAPL emulsification, driven by the surfactant, which enhanced mass transfer and brought the substrate closer to the cells, despite their absence at the interface. This study sheds light on the complex effect of surfactants on Mycobacteria and PAH uptake, revealing an antagonistic effect at low concentrations that ultimately leads to enhanced degradation through emulsification at higher doses. These findings offer valuable insights into optimizing bioremediation strategies in PAH-contaminated environments.

Homogeneously Planar-Exposure LiB Fiber Skeleton Toward Long-Lifespan Practical Li Metal Pouch Cells.

LiB alloy is promising lithium (Li) metal anode material because the continuous internal LiB fiber skeleton can effectively suppress Li dendrites and structural pulverization. However, the unvalued surface states limit the practical application of LiB alloy anodes. Herein, the study examined the influence of the different exposure manners of the internal LiB fiber skeleton owing to the various surface states of the LiB alloy anode on electrochemical performance and targetedly proposed a scalable friction coating strategy to construct a lithiated fumed silica (LFS) functional layer with abundant electrochemically active sites on the surface of the LiB alloy anode. The LFS significantly suppresses the inhomogeneous interfacial electrochemical behavior of the LiB alloy anode and enables the exposure of the internal LiB fiber skeleton in a homogeneously planar manner (LFS-LiB). Thus, a 0.5Ah LFS-LiB||LiCoO2 (LCO) pouch cell exhibits a discharge capacity retention rate of 80% after 388 cycles. Moreover, a 6.15Ah LFS-LiB||S pouch cell with 409.3Whkg-1 exhibits a discharge capacity retention rate of 80% after 30 cycles. In conclusion, the study findings provide a new research perspective for Li alloy anodes.

Coarse grained MD simulation of bulk and interfacial behavior of mixture of CTAB/SDS surfactants.

This study involves simulating the process of inhibiting corrosion through the formation of micelles by surfactants and their deposition on iron (Fe) surfaces. The primary focus is on examining CTAB/SDS mixtures in aqueous solutions with different concentrations. Micelle properties, including size, shape, aggregation number, cluster size, and surfactant diffusion, were calculated and validated with experimental data. The coarse-grained Fe surface was modeled and validated against experimental water contact-angle data. Subsequently, the deposition of CTAB/SDS mixtures on the Fe surface and air-water interface was studied systematically. We found that the relative ratio of CTAB/SDS in the solution directly influences surfactant deposition behavior, which might impact the corrosion inhibition efficiency. All the MD simulations were performed using the GROMACS software with MARTINI2 force field and Martini polar water. The molecules are packed using PACKMOL software. Both NVT and NPT simulations are caried out at temperature and pressure of 303 K and 1 bar respectively, with a nonbonded interaction cut-off (rcut) of 1.1 nm. The LJ potential was shifted from 0.9 nm to rcut, while the electrostatic potential was shifted from 0.0 nm to rcut. For electrostatics, reaction-field coulomb type is used, relative dielectric constant (epsilon-r) and the reaction field dielectric constant (epsilon-rf) are equal to 2.5 and infinity respectively. The dielectric constant below rcut is epsilon-r, and beyond the cut-off is epsilon-rf. Coulomb-modifier used as potential-shift which leads to shift in the coulomb potential by a constant such that it is zero at the rcut. This makes the potential of the integral of the force . The neighbor list was updated every 10 steps, employing a neighbor list cut-off equal to rcut. Using a polar water model, we used a constant time step of 0.02 ps throughout the simulation. The used epsilon-r = 2.5, is recommended for polar water.

Impacts of interfacial bonding between concrete substrate and cast/sprayed HPFRCC on flexural behaviour

The performance of repair materials is greatly enhanced by the integrity of the rehabilitation system, which depends on the behaviour of the boundary or interface bond between the repair material and the concrete substrate. The effects of the implementation of repair materials (casting or spraying), the spraying direction and the roughness of the concrete substrate on the interfacial bond behaviour were experimentally investigated through four-point bending tests on prisms of size 300 × 76.2 × 40 mm. As a first step, 2 cm thick concrete substrates were fabricated with five different types of surface roughness. After 28 days of curing, the repair material (a high-performance (high-ductility) fibre-reinforced cementitious composite (HPFRCC)) was sprayed or poured into specific moulds. The HPFRCC was developed using local materials and had a tensile strain capacity of 3.7%. The spraying direction and surface roughness of the concrete substrate were found to impact the ultimate deflection rate significantly; upward spraying produced the lowest deflection rate and downward spraying the highest. Because beams are often repaired from the lower part and spraying is in the upwards direction, the casting method must be used because of the negative effect of gravity on the interfacial bonding between the concrete substrate and the repair material.

Bearing Characteristics with Effect of Bond–Slip Behavior in Massive Ring-Type Reinforced Concrete Structures

The bond–slip behavior of the steel–concrete interface is critical in reinforced concrete (RC) structures since the bond action is the mechanism that ensures the two materials work in co-operation. However, there is little research considering the bond–slip behavior in massive ring-type reinforced concrete (MRRC) structure bearing analyses due to the complexity of modeling the interfacial behavior. Hence, the influence of the bond–slip behavior on the bearing characteristics of MRRC structures remains unclear. Steel-lined reinforced concrete penstock is such an MRRC structure, composed of steel liner and reinforced concrete and commonly used in diversion pipelines. This paper aims to explore the bearing characteristics considering the bond–slip behavior in the composite penstock by using a promising numerical method, the cohesive zone model. Three interface models were proposed to represent the different interaction conditions at the steel–concrete interface. Moreover, a sensitivity analysis was performed to study the impact of the bond strength on the bond performance and structural behavior. The simulation results showed that the prediction results (steel stress and crack process) considering the bond–slip behavior were in good agreement with the experimental results. The steel stresses near the cracks were smaller and more uniform after considering the bond–slip behavior, since the stresses were no longer concentrated on the crack but distributed in an area near the crack. However, the steel stress differences in these models were within 10%, which means that the bond performance had a limited effect on the structural safety design. The crack widths were greatly influenced by the bond conditions, and the maximum crack width (0.461 mm) in poor conditions was beyond the limiting value (0.3 mm). Consequently, bond–slip behavior must be paid more attention in durability design.

Lattice Mismatch at the Heterojunction of Perovskite Solar Cells.

Lattice mismatch significantly influences microscopic transport in semiconducting devices, affecting interfacial charge behavior and device efficacy. This atomic-level disordering, often overlooked in previous research, is crucial for device efficiency and lifetime. Recent studies have highlighted emerging challenges related to lattice mismatch in perovskite solar cells, especially at heterojunctions, revealing issues like severe tensile stress, increased ion migration, and reduced carrier mobility. This review systematically discusses the effects of lattice mismatch on strain, material stability, and carrier dynamics. It also includes detailed characterizations of these phenomena and summarizes the current strategies including epitaxial growth and buffer layer, as well as explores future solutions to mitigate mismatch-induced issues. We also provide the challenges and prospects for lattice mismatch, aiming to enhance the efficiency and stability of perovskite solar cells, and contribute to renewable energy technology advancements.

Lattice Mismatch at the Heterojunction of Perovskite Solar Cells

Lattice mismatch significantly influences microscopic transport in semiconducting devices, affecting interfacial charge behavior and device efficacy. This atomic‐level disordering, often overlooked in previous research, is crucial for device efficiency and lifetime. Recent studies have highlighted emerging challenges related to lattice mismatch in perovskite solar cells, especially at heterojunctions, revealing issues like severe tensile stress, increased ion migration, and reduced carrier mobility. This review systematically discusses the effects of lattice mismatch on strain, material stability, and carrier dynamics. It also includes detailed characterizations of these phenomena and summarizes the current strategies including epitaxial growth and buffer layer, as well as explores future solutions to mitigate mismatch‐induced issues. We also provide the challenges and prospects for lattice mismatch, aiming to enhance the efficiency and stability of perovskite solar cells, and contribute to renewable energy technology advancements.

Evaluation of Mold Electromagnetic Stirring in Slab Continuous Casting Based on the Steel/Slag Interface Behavior

Evaluation of Mold Electromagnetic Stirring in Slab Continuous Casting Based on the Steel/Slag Interface Behavior

Molecular mechanisms and atmospheric implications of the simplest criegee intermediate and hydrochloric acid chemistry in the gas phase and at the aqueous interfaces

The atmospheric chemistry of Criegee Intermediates has become a frontier research point in environmental pollution in recent years. In this work, quantum chemical calculations and Born-Oppenheimer Molecular Dynamics (BOMD) simulations were employed to explore the gas phase and aqueous interface behavior of the simplest Criegee Intermediate (sCI, CH2OO) and hydrochloric acid (HCl) reaction. Quantum chemical calculations have revealed that the product of ClCH2OOH (CMHP) formation from the CH2OO + HCl reaction without and with water molecule undergoes a barrierless or near barrierless process in the gas phase. The results of the rate coefficients calculated by the master equation indicate that the gas-phase CMHP formation from the reaction of CH2OO + HCl could compete with the hydrolysis of CH2OO with (H2O)2 at the altitude of 15 km. BOMD simulations at the aqueous interfaces show that the CH2OO + HCl reaction occurs through stepwise mechanisms that are distinct from those in the gas phase. Three different interfacial reaction channels were identified: i) CMHP direct formation, ii) water-mediated CMHP formation, and iii) HCl-mediated hydroxymethyl hydroperoxide (HMHP) formation, and completed in picosecond time scales. Considering the harsh reaction conditions between CH2OO and HCl at the interface (i.e., the two molecules must be sufficiently close to form the CH2OO-HCl complex), the route of HMHP formation via the hydrolysis of CH2OO remains the main atmospheric loss pathway of CH2OO at the aqueous interfaces. Interestingly, molecular dynamic simulations in nanosecond time scales reveal that the formed CMHP in the gas phase has a tendency to aggregate with sulfuric acids, ammonia, and water molecules to form stable clusters within 213–278 K. The present results for the CMHP and HMHP formations from the sCI-HCl chemistry in the atmosphere will enhance our comprehension of the atmospheric behavior of Criegee intermediates in urban and marine pollution areas.

Multiscale approach to the characterization of the interfacial properties of micellar casein and whey protein blends and their effects on recombined dairy creams

In this study, whipped cream with blends of micellar casein (MCN) and whey protein (WPI) in different ratios were prepared to investigate the role of protein interfacial behavior in determining foam properties at multiple scales, using theoretical modeling, and microscopic and macroscopic analysis. Fluid force microscopy has been used for the first time as a more realistic and direct means of analyzing interfaces properties in multiphase systems. The adsorption kinetics showed that the interfacial permeability constant of WPI (4.24 × 10-4 s−1) was significantly higher than that of the MCN (2.97 × 10-4 s−1), and the WPI interfacial layer had a higher modulus of elasticity (71.38 mN/m) than that of the MCN (47.89 mN/m). This model was validated via the mechanical analysis of the fat globules in real emulsions. The WPI-stabilized fat globule was found to have a higher Young's modulus (219.67 Pa), which contributes to the integrity of its fat globule morphology. As the ratio of MCN was increased in the sample, however, both the interfacial modulus and Young's modulus decreased. Moreover, the rate of partial coalescence was found to increase, a phenomenon that decreased the stability of the emulsion and increased the rate of aeration. The mechanical analysis also revealed a higher level of adhesion between MCN-stabilized fat globule (25.16 nN), which increased fat globule aggregation and emulsion viscosity, while improving thixotropic recovery. The synergistic effect of the blended MCN and WPI provided the highest overrun, at 194.53 %. These studies elucidate the role of the interfacial behavior of proteins in determining the quality of whipped cream and provide ideas for the application of proteins in multiphase systems.

Effect of Boron on the Interfacial Heat Transfer, Contact Behavior, and Microstructure in the Simulation of Strip Casting of 3.5 Wt Pct Si Non-oriented Silicon Steel

Effect of Boron on the Interfacial Heat Transfer, Contact Behavior, and Microstructure in the Simulation of Strip Casting of 3.5 Wt Pct Si Non-oriented Silicon Steel

A multiscale study of the influence of aggregate type on adhesion at the asphalt–aggregate interface

In order to examine the influence of aggregate type on the asphalt–aggregate interface, the adhesion performance between asphalt and aggregate was investigated at three scales. The pull-out test was conducted on asphalt and three kinds of aggregates at the macroscale to directly estimate the adhesion performance between them. At the microscale, the surface energies between asphalt and limestone, basalt, and andesite were examined through a surface energy experiment, and then the adhesion and debonding work were assessed. At the nanoscale, the interfacial behavior between six mineral compositions (SiO2, CaO, MgO, Al2O3, Fe2O3, and Na2O) of these aggregates and asphalt was determined using molecular dynamics simulation. The correlation of adhesion work at the microscale and nanoscale was further explored to unveil the bonding mechanisms between asphalt and aggregate. The macroscale results indicate that the adhesion force of andesite is slightly greater than that of limestone, probably because andesite has a greater surface roughness than limestone. The microscale results show the best adhesion and water stability between asphalt and limestone. The finding further explains that alkaline aggregates exhibit superior interfacial adhesion to asphalt. The nanoscale results show that the adhesion work of alkaline oxides with asphalt is more significant than that of acidic oxides with asphalt. Limestone and basalt have better adhesion to asphalt due to higher alkaline oxide content, while andesite has poorer adhesion to asphalt due to lower alkaline oxide and higher SiO2 content. The interfacial adhesion work increases from the microscale to the nanoscale by a factor of 2.91–4.75.

Molecular dynamics investigations on the thermophysical property of fatty acid ethyl esters

To develop innovative fuel additives or substitutes and design spray-assisted internal combustion engines, it is important to have a comprehensive understanding of the thermophysical characteristics of biodiesels. Rooted in statistical mechanics, the molecular simulation method can predict the thermophysical properties over a wide range of temperatures and pressures, which overcomes the challenges of experimental measurements and facility restrictions. This work focused on the evaluation of three classical force fields (FFs) in terms of their ability to predict the thermophysical properties of ethyl-caprylate (EtC8:0), ethyl-caprate (EtC10:0), ethyl-laurate (EtC12:0), ethyl-myristate (EtC14:0), ethyl-palmitate (EtC16:0), and ethyl-stearate (EtC18:0) within a temperature range of (303.15 to 403.15) K and pressures up to 100 MPa. The Optimized Potential for Liquid Simulations–All atom and its modification (OPLS and L–OPLS) and Transferable Potential for Phase Equilibria–United Atom (TraPPE–UA) FFs were evaluated. These findings demonstrated that the L–OPLS FF, when applied in the isobaric-isothermal (NPT) and canonical ensembles (NVT), effectively replicated the experimental data and semi-empirical models for density, viscosity, diffusivity coefficient, and interfacial behavior at elevated temperatures and pressures. Moreover, the utilization of the radial distribution function, radius of gyration, and end-to-end distance distribution in the analysis of liquid conformations allowed for a comprehensive investigation of the microscopic structure. This work provides the theoretical methodologies and empirical evidence for the advancement of biodiesel and other petrochemicals.

Topological isomerism design of Demulsifiers: A fusion of molecular dynamics simulation and experiment

Demulsifiers are crucial for enhancing crude oil extraction and transportation efficiency by facilitating the separation of oil–water emulsions. However, research conducted on the design and synthesis of demulsifiers based on the results of molecular dynamics simulation remains scarce. Herein, we designed eight block polyethers, and explored their interfacial behaviors at the oil–water interface via molecular dynamics simulation. Correspondingly, eight block polyether demulsifiers were synthesized, and their interface properties were tested. The simulation results were consistent with the experimental results, indicating that the energy of simulation systems could be efficiently reduced by designed molecules, and that the prepared demulsifiers with the same structure could achieve effective demulsification correspondingly. Based on the simulation and experimental results, a “hand-shaped” demulsification mechanism model was proposed. The demulsifiers with hydrophobic “palm” and hydrophilic “fingers” demonstrated a more efficient performance in demulsification. The hydrophobic “palm” was stable in the continuous oil phase, and the hydrophilic “fingers” could attract dispersed water droplets to aggregate, facilitating demulsification. The study also finds that longer hydrophilic “fingers” exert stronger molecular force. Combining molecular dynamics simulation and experiment significantly accelerates the development of new demulsifiers, highlighting the utility of this approach in the research on demulsifiers.

Suppressing interfacial reactions and burn-on defects in sand casted 13Cr9Mo1VNb steel castings. Part I: a novel MgO-chromite hybrid material

Addressing the significant issues of sand burn-on defects and interfacial reaction in sand casted 13Cr9Mo1VNb steel castings, which notably compromise the quality of the steel castings, remains a persistent challenge. The interfacial behaviors between the novel mixed sands and the steel grade were investigated under various sands. The sintering behavior of the sands was also studied without liquid steel at various holding time. In the absence of the influence of molten steel, sintering of mixed chromite-MgO does not undergo solid-solid reaction, with no detected presence of liquid phase and 2MgO·SiO2. The mixed sands undergo sintering reactions upon contact with molten steel, yet no liquid phase is detected. This is primarily attributed to the chemical reaction between MgO and the liquid phase, resulting in the formation of forsterite, leading to the near-complete liquid phase consumption. Magnesia grains can suppress the liquid phase sintering of chromite by 13Cr9Mo1VNb, thus weakening its sintering performance. The presence of 2MgO·SiO2, which exhibits excellent resistance to slag (liquid phase) and steel liquid corrosion, impedes the rising of the liquid phase. Consequently, this reduces the thickness of the adhesive layer and suppresses metal penetration. The production of 2MgO·SiO2 diminishes with the escalation of MgO addition, which increases adhesive thickness and metal penetration as the magnesia content rises. Within the scope of this study, the incorporation of 20 % MgO is suggested to mitigate burn-on defects, which may represent an advantageous selection.

Elucidating the construction and modulation of built-in electric field in the oxygen evolution reaction

The construction of a built-in electric field (BIEF) is considered to be an effective strategy for enhancing catalyst performance due to its critical role in optimizing adsorption of reactants and key intermediates, as well as its positive impact on interface behavior. Herein, a strategy is developed to elucidate the correlation between oxygen evolution reaction activity and the BIEF and its strength by constructing and enhancing the BIEF through incorporating manganese into Co3O4@NiFe-LDH p-n heterojunction. This Co3O4@NiFe-LDH p-n heterojunction generates a BIEF that effectively regulates electronic structure, facilitates rapid electron transfer, induces alterations in the chemical microenvironment, and modulates intermediate adsorption energy. Notably, when hetoroatomic Mn is incorporated into the p-n heterojunction, particularly encapsulated within NiFe-LDH, a more pronounced enhancement for BIEF is observed. Benefiting from this strong BIEF, Co3O4@Mn/NiFe-LDH exhibits excellent OER activity and stability with an overpotential of only 209 mV at 50 mA cm−2, a Tafel slope of 57 mV dec−1, and stable operation for 110 h at approximately 10 mA cm−2. Moreover, density functional theory (DFT) calculations further confirms that the construction and reinforcement of the BIEF can effectively accelerate the electron transfer rates, adjust the metal d-band center, optimize intermediates adsorption properties, and reduce the reaction energy barriers.

ANALYSIS OF THE MIXED ELASTOHYDRODYNAMIC LUBRICATION CHARACTERISTICS OF DOUBLE CIRCULAR ARC GEARS CONSIDERING MICRO-MORPHOLOGY

Different machining methods result in diverse morphologies on the surface of gears. Under mixed lubrication, the friction and contact behavior of the real morphology interface becomes more complex. This study aims to analyze the influence of different process tooth surface micro-morphologies on the lubrication performance of the meshing area of double circular arc gears. Focusing on elastohydrodynamic lubrication (EHL) characteristics of the double circular arc gears as the research object, the study involved measuring the three-dimensional morphology of the meshing position of the double circular arc gears. Non-Gaussian simulation technology was then used to characterize the micromorphology of the tooth surface resulting from different processes (i.e. hobbing process and skiving process). The tooth surface suction speed was determined based on the meshing characteristics of double circular arc gears. Based on the theory of point contact EHL, Reynolds equation and film thickness equation considering micromorphology were derived, and numerical solutions were obtained using the multi-grid method. A point contact EHL model for double circular arc gears was established considering the micromorphology of tooth surfaces in different processes. Results show that, the oil film pressure is positively correlated with rotational speed and torque. The oil film thickness is positively correlated with rotational speed, and negatively correlated with input torque. The negative of micro-morphology on the tooth surface on the lubrication performance could lead to an increase in pressure fluctuations and the absence of the second pressure peak. The uneven distribution of oil film and the lager roughness value could result in obvious fluctuations. The lubrication performance of the contact area in the gear hobbing process is superior to that in the gear skiving process. This study lays the foundation for further exploring the coupling characteristics between the double circular arc gear transmission system and elastic fluid dynamic lubrication. Keywords: Double circular arc gears, Point contact, Mixed EHL, Lubrication characteristics, Micro- morphology.

Local Microenvironment Modulation of Pt0/Pt2+ Nano-clusters Inducing Synchronous Mass Transfer Effect to Boost Catalytic Ozonation

Rational catalyst structure design is expected to solve the low O3 utilization and poor molecular mass transfer efficiency in heterogeneous catalytic ozonation (HCO). Herein, Pt/CMK-3 catalyst with confined space to enhance mass transfer was synthesized and employed for CH3SH removal. Unlike fully free diffusion in 0~2.0wt.% Pt/CMK-3 and bulk phase diffusion in 10.0wt.% Pt/CMK-3, removal efficiency of 5.0wt.% Pt/CMK-3 was significantly improved to 97.0%, which was attributed to the effective interfacial diffusion of O3 and CH3SH through local microenvironment modulation of Pt0/Pt2+ nanoclusters (NCs) inducing synchronous mass transfer. Experimental and DFT calculations confirmed the strong electronic interactions between O3 and Pt0 facilitated charge redistribution and preferential O3 activation. AIMD simulation demonstrated that the synchronous difference in mean-square displacements (MSD) and diffusion coefficient (Dc) of CH3SH (Dc=0.022) and O3 (Dc=0.0046) in the confined Pt/CMK-3 system could facilitate CH3SH migrate to Pt2+ through interfacial diffusion. Especially, the d-orbital electrons of Pt NCs interact sequentially with p-orbital electrons of CH3SH and O3 to maintain redox of Pt0/Pt2+. This study provides novel insights on effective mass transfer and kinetic properties of gaseous reaction between oxidant and pollutant by constructing unique interfacial diffusion behaviors.

Revealing the grain boundary effect on interfacial adhesion in polycrystal Fe/Ni interfaces by using a multi-scale CZM-CPFEM approach

In layered structure, interface plays a significant role in property improvement, whereas its multiple factors at various length scales restricted further understanding. Previous research found a novel grain boundary (GB)-interface interaction: crack initiation locally occurred at the junctions between pre-existing GBs and interface. This leads to decreased interfacial strength. To clarify the mechanisms of such GB-interface interaction, the present study proposed a multi-scale cohesive zone model-crystal plasticity finite element method (CZM-CPFEM) model to investigate the effect of pre-existing GB on intrinsic bonding strength at atomic scale and interfacial stress distribution at micro scale, respectively. At atomic scale, interfacial fracture criteria were modelled according to Molecular Dynamics (MD)-based traction-separation relationships. The accuracy of CZMs was improved by considering both isothermal holding and tilting configuration effects. At micro scale, a practical interfacial microstructure was used to construct CPFEM models. Tensile simulations showed that the local stress concentration occurred at junctions, attributed to the anisotropic plastic deformation behaviours across the GB. On the other hand, weak bonding adhesion at the junction only affects the local crack initiation strength, showing insignificant impacts on the overall interfacial fracture behaviour.

Microstructure, mechanical properties, and fracture behavior of multi-core through steel wire reinforced brass composite rod produced by a solid-liquid continuous casting and composite technique

A multi-core through steel wire reinforced brass composite rod was fabricated using a solid-liquid continuous casting and composite technique. Microstructure evolution, interface, mechanical properties, and deformation behavior of the composite rod during the room temperature tensile process were studied. The results showed that the steel wires in the composite rod· were distributed in a regular hexagonal shape, forming a brass/steel interface with good metallurgical bonding. After annealing at 700°C for 1h, the tensile strength of the composite rod was 376MPa, and the elongation to failure was 46.3%, whose tensile strength was 21% higher than that of the brass cladding single steel wire composite rod with the same steel percentage. During uniform tensile deformation, each steel wire in the composite rod experienced a consistent and uniform tensile stress. When the tensile deformation became unstable, the central steel wire experienced the highest level of tensile stress, initially leading to the occurrence of necking and fracture. As the tensile strain increased, the brass grains underwent twisting and rotation. In addition, the steel grains were elongated along the tension direction, and the number of low-angle boundaries increased. The straight brass/steel interface was transformed into a wavy pattern with a good bonding interface, indicating that the composite rod exhibited excellent synergetic deformation capability. The mixing laws based on hybrid effects have good applicability to multi-core through steel wire reinforced brass composite rod, with a strength error of less than 7%.