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The frequent detection of 6:2 chlorinated polyfluorinated ether sulfonate (F-53B) in various environments has raised concerns owing to its comparable or even higher environmental persistence and toxicity than perfluorooctane sulfonate (PFOS). This study investigated the plasma degradation of F-53B for the first time using a water film plasma discharge system. The results revealed that F-53B demonstrated a higher rate constant but similar defluorination compared to PFOS, which could be ascribed to the introduction of the chlorine atom. Successful elimination (94.8–100 %) was attained at F-53B initial concentrations between 0.5 and 10 mg/L, with energy yields varying from 15.1 to 84.5 mg/kWh. The mechanistic exploration suggested that the decomposition of F-53B mainly occurred at the gas-liquid interface, where it directly reacted with reactive species generated by gas discharge. F-53B degradation pathways involving dechlorination, desulfonation, carboxylation, C-O bond cleavage, and stepwise CF 2 elimination were proposed based on the identified byproducts and theoretical calculations. Furthermore, the demonstrated effectiveness in removing F-53B in various coexisting ions and water matrices highlighted the robust anti-interference ability of the treatment process. These findings provide mechanistic insights into the plasma degradation of F-53B, showcasing the potential of plasma processes for eliminating PFAS alternatives in water. [Display omitted] • A comparison of PFOS and F-53B degradation using the plasma process was conducted. • The degradation of F-53B mainly occurs at the plasma-liquid interface. • Plasma treatment is effective for removing F-53B in various water matrices. • The mechanisms of F-53B degradation in the plasma system were proposed. • The toxicity of the products was reduced following the plasma treatment. [ABSTRACT FROM AUTHOR]

This study explores the growth behavior and rate-controlling processes of intermetallic compounds at Ag/Zn diffusion couple interfaces. Through experimental observations and quantitative analysis, we identify three distinct intermetallic compounds: β-AgZn, γ-Ag 5 Zn 8 , and ε-AgZn 3. We analyze the kinetics of intermetallic compound growth to elucidate the mechanisms governing thickness growth in terms of interdiffusion and interface reactions. The rate-controlling process varies with temperature; volume diffusion controls layer growth at 573–593 K, while both volume diffusion and interface reaction contribute at 623–673 K. Additionally, we evaluate the activation enthalpies of parabolic coefficients, providing insights into the temperature dependence of growth kinetics and quantitation. This comprehensive analysis clarifies the intricate mechanisms underlying intermetallic compound formation, offering valuable implications for material performance and processing optimization in various applications. [Display omitted] • We identified the formation of three intermetallic compounds (β-AgZn, γ-Ag 5 Zn 8 , ε-AgZn 3) at Ag/Zn interfaces. • The temperature dependence of the diffusion coefficient is higher compared to that of the interface reaction rate. • We evaluated activation enthalpies of parabolic coefficients for the growth, elucidating the temperature dependence. • Understanding the mechanisms governing intermetallic compound formation is crucial for material performance optimization. [ABSTRACT FROM AUTHOR]

W-Si-C composites with high relative densities and good mechanical and wear properties were successfully prepared by spark plasma sintering. The influence of SiC content on the relative density, microstructure, mechanical properties and wear characteristics was investigated. The results indicated that the reaction between SiC and W at their interface produced W2C and W5Si3. SiC also reacted with oxygen impurities at the W grain boundary to form SiO2. The purification of the grain boundaries of W was carried out by SiO2 synthesis. Reactive sintering reduces the free energy of the system and facilitates the densification process of W-Si-C composites. This results in a significant increase in the relative density of W-Si-C composites, which reaches a maximum of 98.12%, higher than the 94.32% of pure tungsten. The hardness significantly increases from 4.33 GPa to 8.40 GPa when the SiC content is 2 wt% compared to pure tungsten due to the generation of the hard ceramic phase and the increase in relative density. The wear resistance of the W-Si-C composites was significantly improved with little SiC addition. The wear rate significantly decreased from 313.27 × 10−3 mm3/N·m of pure tungsten to 5.71 × 10−3 mm3/N·m of W-0.5 wt% SiC. SEM analyses revealed that the dominant wear mechanism of pure tungsten was attributed to fatigue wear, while that of W-Si-C composites was due to abrasive wear.

This study investigates the wetting characteristics, interface microstructure evolution of equiatomic GaInSnBiZn HEA on Cu under high vacuum with sessile drop method to extend its electronic packaging applications. Optimal conditions involve a 350 °C temperature maintained for ∼20 min to prevent Bi loss, resulting in a contact angle inversely proportional to temperature and reaching a minimum of ∼15.6°. A dual-layer of Cu 9 Ga 4 and CuGa 2 forms at the HEA/Cu interface, consistent with thermodynamic predictions, featuring lower activation energy and growth driven by bulk alloy diffusion. Base on the interface microstructures, Cu 9 Ga 4 and CuGa 2 act as diffusion barriers, restricting the movement of other elements while promoting the accumulation of Zn at the interface. The wetting mechanism may be determined by the oxide (Cu 2 O) removal reaction (i.e., reaction between Ga and Cu 2 O). [ABSTRACT FROM AUTHOR]

[Display omitted] • After BHA was adsorbed onto the scheelite surface o, the surface roughness and water contact angle increased by 0.35 nm and 13.14°. • Added BHA repelled water adsorbed onto the Ca sites on the scheelite surface via O atoms in C-N-O bonds, an adsorption energy of −56.26 kJ/mol. • After AIMD simulation, the hydration layer on the surface of scheelite became tighter, and the BHA Ca complex detached from the mineral surface. • AIMD calculations have shown great potential in the analysis of the complicated interface interactions. To explain the low recovery rate of scheelite during flotation using benzohydroxamic acid (BHA), we performed experiments and AIMD simulations. The results showed that scheelite floated only 50 % of BHA. The adsorption capacity of BHA on the scheelite surface was 1.63 × 10−5 mol/g, which caused the surface potential of scheelite to become negative, with a change of −10.5 mV at pH 9.05. After BHA adsorbed onto the scheelite surface, the surface roughness increased by 0.35 nm, and the water contact angle of the scheelite surface increased by 13.14°. Moreover, 1.76 % N was detected, representing BHA molecules, BHA-Ca complexes, and H-bonded BHA species·H 2 O adsorbed onto surface calcium ions and between adjacent calcium ions, while free, unadsorbed H 2 O molecules formed clusters. The added BHA repelled water adsorbed onto the Ca sites of the scheelite (1 1 2) surface via O atoms in C-N-O structure with an adsorption energy of −56.26 kJ/mol. AIMD simulations at 300 K revealed that temperature changed the adsorption of flotation agent molecules on scheelite surfaces, including the densification of hydration layers and the separation of BHA-Ca complexes from the scheelite surface. [ABSTRACT FROM AUTHOR]

• A novel sandwich-like membrane is designed and prepared for catalysis. • Membrane is acted as interface material for catalytic reaction. • Reaction continuously runs at the interface between oil and water. • A novel reaction technology is designed and applied for interface catalysis. It is of significance to improve the interfacial catalytic performance of noble metal nanocatalysts in heterogeneous reactions and to achieve real-time oil-water phase separation to reduce the separation and purification process. In the current work, a sandwich-like polymeric membrane was prepared, with a core layer of poly(vinylidene fluoride) (PVDF)/poly(methacrylic acid) (PMAA) microspheres/Pd nanoparticles as the reaction center, and a hydrophilic semi-interpenetrating polymer network (semi-IPN) as well as a hydrophobic PVDF as shells for the benzaldehyde green preparation. The process proceeded by using the sandwich-like membrane to catalyze the interface reaction between the organic phase of benzyl alcohol and the aqueous phase of H 2 O 2 and the effect factors such as reaction temperature, feed flow rate, the initial benzyl alcohol concentration and catalyst dosage were investigated to get the optimal oxidation conversion and selectivity. Results indicated that the interface reaction went well, without the aggregation and leaching of Pd nanoparticles from membrane support. Furthermore, the product benzaldehyde could be selectively transported to the organic phase. The sandwich-like catalytic composite membrane integrates the catalysis with phase separation, providing a new strategy for the preparation of the chloride-free benzaldehyde. What's more, the sandwich-like catalytic membrane acts as an ideal option for a large-scale catalysis application with integrated advantages of high activity, convenient operation and omitted separation of catalysts and products from heterogeneous catalytic interfacial reaction system. A novel sandwich-like membrane and technology for catalysis. [Display omitted] [ABSTRACT FROM AUTHOR]

Taking the high volume fraction SiCp/6061Al-based composite material prepared by the powder metallurgy method under different sintering temperatures and holding times as the research object, the microstructure and interface actions are investigated by X-ray diffractometer, scanning electron microscope, transmission electron microscope, etc. The results show that as the sintering temperature increases, the interface reaction between SiC and Al intensifies, producing brittle phase Al4C3 and MgAl2O4 and MgO interface products. The nucleation and growth of Al4C3 are controlled by the sintering temperature and time. When preparing large-size workpieces with high volume fraction SiCp/6061Al-based composite materials, the sintering temperature should be controlled below 6 7 0 ∘ C, and the holding time should not exceed 24 h. [ABSTRACT FROM AUTHOR]

• The corrosion between the slag-line and mold flux under the applied external electric field are studied for the first time. • An anti-corrosion protective layer is formed at the outside surface of the slag-line under the negative electric field. • The dissolution and corrosion behavior of slag-line can be control by incorporating interfacial electrochemical reactions. • The external electric field maybe used as a new technology to deal with slag-line corrosion of SEN. The corrosion mechanisms that occurred between the slag-line and mold flux under the applied external electric field are studied. The results show that the slag-line can be effectively protected when the slag-line is connected to the negative electrode, and the graphite as an auxiliary electrode is connected at positive potential. Under the applied negative electric field, a thick protective adhesion layer is formed on the surface of the slag-line due to the electrochemical reactions. Additionally, the slag-line material is further reacted with surface of the formed protective layer and generates another interface reaction layer. Under the effect of double protective layers, the slag-line can be perfectly devoid of corrosion attack under the negative electric field. The performance of the slag-line and the production time of the whole continuous casting can be improved. The external electric field is expected to be a new technical approach to alleviate corrosion of the SEN. [ABSTRACT FROM AUTHOR]

In this research, a kind of 70-47-25% B4C/2024Al functionally graded materials (FGMs) were prepared by squeeze casting. The interfacial microstructure, precipitate characteristics and mechanical properties of B4C/2024Al FGMs were mainly studied. It was found that there was a small amount of interfacial reaction between B4C particles and Al. Mg and O elements segregated at the Al-B4C interface and MgO was formed. Under the same heat treatment conditions, the types and sizes of precipitates in different gradient layers were found to be different. Different amount of Mg segregation at the B4C-Al interface resulted in different proportion of Cu and Mg in 2024Al matrix and it makes the precipitation regions of 25 vol%, 47 vol% and 70 vol% B4C/2024Al locate in S, θ + S and θ respectively. The test results of basic properties indicated that the strength and plasticity of 70-47-25% B4C/2024Al FGMs show gradient changes. The bending stresses of 70%, 47% and 25% B4C/2024Al composites can reach 591.5 MPa, 953.4 MPa and 700.7 MPa respectively. And the elastic modulus are 240.3 GPa, 170.9 GPa and 130.7 GPa respectively. The results of this research will provide theoretical guidance for the interface structure design and heat treatment process of high strength B4C/Al composites.

Lithium-ion batteries (LIBs) are widely used in portable electronic devices, electric vehicles and large scale energy storage, due to their considerable energy density, low cost and long cycle life. However, traditional liquid batteries suffer from safety problems such as leakage, thermal runaway and even explosion. Part of the issues are caused by lithium dendrites puncturing the liquid electrolyte during cycling. In order to achieve the objective of higher safety and energy density, a rigid solid-state electrolyte (SSE) is proposed instead of liquid electrolyte (LE). Thereinto, sulfide SSEs have received of the most attention due to their high ionic conductivity. Among all the sulfide SSEs, argyrodite SSEs are considered to be one of the most promising solid-state electrolytes due to their high ionic conductivity, high thermal stability and good processablity. On the other hand, lithium metal is an ideal material for anode because of its high specific energy, low potential and large storage capacity. However, interfacial problems between argyrodite SSEs and the anode (interfacial reactions, lithium dendrites, etc.) are considered to be important factors affecting their availability. In this mini review, we summarize the behavior, properties and problems arising at the interface between argyrodite SSEs and anode. Strategies to solve interface problems and stabilize interfaces in recent years are also discussed. Finally, a brief outlook about argyrodite SSEs is presented.

The stability of diamond/aluminum composite is of significant importance for its extensive application. In this paper, the interface of diamond/aluminum composite was modified by adding nanoscale W coating on diamond surface. We evaluated the corrosion rate of nanoscale W-coated and uncoated diamond/aluminum composite by a full immersion test and polarization curve test and clarified the corrosion products and corrosion mechanism of the composite. The introduction of W nanoscale coating effectively reduces the corrosion rate of the diamond/aluminum composite. After corrosion, the bending strength and thermal conductivity of the nanoscale W-coated diamond/aluminum composite are considerably higher than those of the uncoated diamond/aluminum composite. The corrosion loss of the material is mainly related to the hydrolysis of the interface product Al4C3, accompanied by the corrosion of the matrix aluminum. Our work provides guidance for improving the life of electronic devices in corrosive environments.

The complex interface reactions are crucial to the performance of the Li 2 MnO 3 cathode material. Here, the interface reactions between the liquid electrolyte and the typical surfaces of Li 2 MnO 3 during the charging process are systematically investigated by ab initio molecular dynamics (AIMD) simulation and first-principles calculation. The results indicate that these interface reactions lead to the formation of hydroxide radicals, oxygen, carbon dioxide, carbonate radicals, and other products, which are consistent with the experimental findings. These processes primarily result from the conversion of the stable closed-shell O 2- into reactive oxygen ions by electron loss. All surfaces exhibit some degree of layered- and spinel-like phase transitions during the AIMD simulations, consistent with the experiment. This is mainly attributed to the decrease in the Mn-O bond strength and the increase in the Li/O ion vacancy concentration. This study offers valuable theoretical insights into the interface reaction between lithium-rich cathode materials and liquid electrolytes.

• A high-temperature visualisation technology was applied to quantify the formation and growth of the corrosion peak at 1600 °C. • The relationship between the peak area and C/S ratios of melt was clarified, thus evaluating corrosion index of alumina ceramics in contact with the melts. • The evolution models for the area, height, and FWHM of the corrosion peak with change in melt compositions were proposed. Alumina ceramics undergo quasi-volcanic corrosion at the melt-air interface, which causing severe damage. However, the growth behaviour of quasi-volcanic corrosion requires further investigation. Here, high-temperature visualisation technology was used to characterise and quantify quasi-volcanic corrosion at the melt-air interface at 1600 °C. An evolution model of the corrosion peak area with changes in the melt compositions was also established. The formation and growth of the corrosion peak is closely related to the temperature, soaking time and the dissolution reaction; quasi-volcanic corrosion occurs at ≥ 1600 °C, and is visibly different from normal corrosion at a three-phase interface. The peak height exhibits competitive evolution with the full width at half maximum of the peak. The obtained evolution of the corrosion peak and relationship between the corrosion area and the C/S ratios of the melts can support for prolonging the service life of alumina ceramics. [ABSTRACT FROM AUTHOR]

While reactions between ions and neutral molecules in the gas phase have been studied extensively, reactions between molecular ions of same polarity remain relatively unexplored. Herein we show that reactions between fragment ions generated in the gas phase and molecular ions of the same polarity are possible by soft‐landing of both reagents on surfaces. The reactive [B12I11]1− anion was deposited on a surface layer built up by landing the generally unreactive [B12I12]2−. Ex‐situ analysis of the generated material shows that [B24I23]3− was formed. A computational study shows that the product is metastable in the gas phase, but a charge‐balanced environment of a grounded surface may stabilize the triply charged product, as suggested by model calculations. This opens new opportunities for the generation of highly charged clusters using unconventional building blocks from the gas phase. [ABSTRACT FROM AUTHOR]

To solve the limitations of clogging and erosion of the submerged entry nozzle (SEN) for the production of high-quality special steel, the chemical reactivity between different alloys and the SEN and the interface reaction between alloys and the SEN controlled by an electric current pulse (ECP) were examined in this study. Results revealed that the chemical reactivity between different alloys and the SEN is different. For example, the reactivity between rare-earth metal and the SEN was strong, while that between Al and the SEN was extremely weak. At the same time, some differences between the clogging and interface reaction by ECP control were observed. Typically, at the positive electrode of the SEN, when a stable and dense clogging layer is formed, the internal SEN was effectively protected. However, at the negative electrode of the SEN, the decarburization rate of the SEN was accelerated by ECP, probably leading to a vicious circle of accelerated clogging and erosion of the SEN. Therefore, in the future, issues of clogging, erosion, infiltration, and decarbonization between active alloys and the SEN in the casting process may be solved and regulated by using the positive electric field of ECP. Meanwhile, the gain effect of ECP also helped to promote the homogenization of molten steel. [ABSTRACT FROM AUTHOR]

The ultrasonic-assisted soldering joint of Cu/Al with different contents of copper particles added to solder powder at low temperature was studied. In this study, 15%SAC0307 solder powder with a diameter of 500 nm, different amounts copper particles with a diameter of 500 nm were mixed with zinc particles of a diameter of 45 μm to fill the Cu/Al joint, and the soldered was heated to 240 °C for ultrasonic-assisted under the environmental atmosphere. Successfully achieved micro-joining of Cu/Al under ultrasonic-assisted at low-temperature. The results have shown that, when the copper content was 0%-15%, two layers of complete and continuous CuxZny compounds were formed at the copper side interface. When the copper content was more than 15%, the IMC layer of the copper side interface was not obvious, and a large amount of CuxZny compounds were formed near the copper side. The base metals on the aluminum side formed a solid solution combination with zinc. When the addition amount of copper powder was 15%, the soldering seam was smooth and flat, the defect between balls was not obvious, and the IMC was uniformly distributed, so the average shear strength reached the maximum value of 47.37 MPa.

In this study, the reactivity between nozzle and submerged entry nozzle and alloy elements in the steel (Al and Ce) under different electric field conditions was investigated. The results show that the decarburization of the nozzle is an important factor affecting the clogging behavior and steel quality. The external electric field directly affects and changes the decarburization, clogging, and reaction behavior between the nozzle and alloy in the steel. If the chemical reaction force between alloys and the nozzle is greater than the applied electric field force in actuality, the clogging will also occur on the submerged entry nozzle. In the future, this new method of controlling and changing the interfacial electric fields can be used to solve the problem of decarburization and clogging of the submerged entry nozzle. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) has been widely existed in the soil, which has great influence on the adsorption of heavy metals by minerals. In this paper, the effects of DOM on Cd (II) adsorption by calcite were studied. In the presence of DOM (5 mg/L, 10 mg/L, and 20 mg/L), the maximum sorption of Cd (II) by calcite reduced from 48.94 mg/g to 44.14 mg/g, 28.11 mg/g, and 22.30 mg/g, respectively. The characterizations (XRD, SEM, XPS, FTIR, 3D-EEM, and UHPLC-Q-Orbitrap) were used to further study the mechanism about the effects of DOM on the adsorption of Cd (II) by calcite. These results showed calcite exhibited a significant adsorption capacity for Cd (II) at pH = 6.0, and CdCO3 was formed on the surface of calcite after calcite reaction with Cd (II). Meanwhile, the fractionation of DOM by calcite could change the binding characteristics of DOM to calcite, which would increase the migration of Cd (II) in the solution. After the reaction of DOM with Cd (II) and calcite, Cd (II)-DOM complex was formed, and part of calcite was dissolved in the solution which would further increase the migration of Cd (II) and decrease the adsorption of Cd (II) by calcite. This paper might help further understand the effect of calcite and DOM on the environmental behavior of Cd (II) in the soil environment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, thermodynamic calculation and different binary slag interface reaction experiments are used to study the reaction characteristics of different binary slag. The differences in melting process, wetting and reaction behavior were studied. The wetting angle of acidic slag is higher than that the corresponding basic slag. The variation of wetting angle between different binary slag is relatively small. The variation range is only 18 °C. In the melting and reaction process of different binary slag interfaces, the permeation and reaction of the CaO - MgO and CaO - SiO2 interfaces are relatively sufficient. However, there is no obvious chemical reaction between CaO - Al2O3 and Al2O3 - MgO, and the composition and interface separation among each component are more obvious.

The effect of atomic-layer-deposition (ALD)-derived Al2O3 passivation layer on the interface quality of Er2O3/Al2O3/InP laminated stacks and the improvement of electrical performance has been investigated systematically. The chemical bonding states measured by high-resolution X-ray photoelectron spectroscopy (XPS) reveal that the ALD-derived Al2O3 passivation layer can effectively inhibit the diffusion of substrate elements to optimize the interface quality. Electrical characterizations show that the optimized sample has demonstrated improved electrical properties, including the large dielectric constant of 20 and the suppressed leakage current density of 4.10 × 10−7 cm2. In addition, the leakage current conduction mechanisms are also investigated as a function of thickness of Al2O3 passivation layer. The optimized interface state density extracted from the conductance method has reduced from 1.30 × 1012 eV−1cm2 of Er2O3/InP to 7.27 × 1011 eV−1cm2 of Er2O3/Al2O3/InP by adjusting the passivation layer thickness. As a result, it can be also confirmed that the passivation treatment is beneficial to inhibit the element’s diffusion and optimize the interface quality, significantly controlling the capacitor degradation caused by the leakage current through the stacked oxide layer. [ABSTRACT FROM AUTHOR]

The coal gasification slag is used as fine aggregate to replace natural sand aggregate for preparing cement mortar. The physical and mechanical properties and microstructure development of coal gasification slag cement mortar are researched. The interface reaction mechanism between coal gasification slag and cement paste is analyzed by scanning electron microscope, energy dispersive spectrometer and mercury intrusion porosimeter. The results show that the mechanical strength of coal gasification slag cement mortar is lower than that of natural sand cement mortar before 28 days, but it continues increasing after 28 days and exceeds that of natural sand cement mortar. Additional Ettringite and C-S-H gel generated by the interface reaction of coal gasification slag aggregate under the activation of cement paste, which reduces the porosity of cement mortar and enhances the bonding performance between coal gasification slag aggregate and cement paste in cement mortar, are responsible for the continuous increase in the later mechanical strength of coal gasification slag cement mortar. [ABSTRACT FROM AUTHOR]

65 % (volume fraction，the same below) SiCp/A356 composites with different holding time (6,12 h) were prepared by powder metallurgy. The microstructure and interfacial reaction of 65% SiCp/A356 composites were characterized by Optical Microscopy(OM)，X ray Diffraction(XRD)，Scanning Electron Microscopy(SEM) and Transmission Electron Microscopy(TEM). The results show that at 630 °C hot pressing temperature, the density of the material after holding for 12 h is better than that of holding for 6 h，and there is obvious precipitation of Si phase; slight interfacial reaction occurs, the reaction product is mainly Mg Ab O4, and no harmful phase AI4C3 is found. The elastic modulus，thermal conductivity and thermal expansion coefficient of the material were 210 GPa, 216 W/(m • K) and 7. 3 X 10-6/°C (50 300 °C)respectively. [ABSTRACT FROM AUTHOR]

Interdiffusion and solid-solid phase reaction at the interface between thermoelectric (TE) materials and the electrode critically influence interfacial transport properties and the overall energy conversion efficiency during service. Here, the microstructural evolution and diffusion mechanisms at the interfaces between the most widely used Bi 2 Te 3 -based TE materials, n-type Bi 2 Te 2.7 Se 0.3 (BTS) and p-type Bi 0.5 Sb 1.5 Te 3 (BST), and Ni electrodes were investigated at atomic resolution using spherical aberration-corrected scanning transmission electron microscopy (STEM). The BTS(0001)/Ni and BST(0001)/Ni interfaces were constructed by depositing Ni nanoparticles on mechanically exfoliated BTS and BST bulk materials and subsequent annealing. The interfacial reaction is initially dominated by Ni diffusion into the TE matrix to form NiAs-type NiM intermetallics, while Ni trans-quintuple-layer diffusion only occurs in Sb-rich BST. The Bi-rich BTS is more influenced by the Ni-Te preferential reaction, resulting in NiM abnormal grain growth and the formation of tilted and rotated interfaces. Bi diffusion into the BTS matrix forms a Bi double layer at the interface or Bi 2 [Bi 2 (Te,Se) 3 ] as the annealing temperature increases, while Bi diffusion into the Ni thin film greatly accelerates the interfacial reaction rate, as elucidated by in situ heating STEM. The results provide essential structural details to understand and prevent the degradation of TE device performance.

ZnCl2 and SnCl2 were added to the AlF3-CsF eutectic flux, which can be used for connecting aluminum alloy sheet by self-brazing at medium temperature. The influence of the amount of ZnCl2 and SnCl2 and the size of the T-joint area on the interface microstructure and the self-brazing joint mechanical properties was investigated. The interface microstructure, chemical compositions, defects and tensile fractography of the self-brazing joints were analyzed by metallographic microscope, scanning electron microscope and energy dispersive spectroscopy. The results show that the joints are soundly bonded when both the mass fractions of ZnCl2 and SnCl2 are about 4%; the replacement reactions between Zn2+, Sn2+ of flux and Al atoms of base metal occur during brazing, then the liquid metals of Sn and Zn appear, a great degree of Zn which has high solid solution with Al spreads rapidly to the base metal; Sn is distributed along the interface forming a low melting point metal layer with Zn and Al; the brazing of joints with small area can be realized easily; there are a lot of dimples on the fracture surface and the tensile strength of the brazing joint reaches (58±5)MPa.

One of the key issues for composites is the formation mechanism and stability of the interface. Experimental technology and first-principles calculations with quasiharmonic approach considering the phonon and thermal electronic contribution are adopted to clarify the thermodynamics and thermal stress of the interface of tungsten carbide particle reinforced iron matrix (WC P /Fe) composites under finite temperature. The most favorable formation path of Fe 3 W 3 C at the interface is 3Fe+2WC + W 2 C→Fe 3 W 3 C+2C + W. For WC P /Fe and WC P /Co composites, the thermal stress of Co 3 W 3 C is smaller than Fe 3 W 3 C as the transition phase of the interface, and Fe is less suitable to be applied as the matrix of composites than Co. Our research provides significant guidance to improve the interfacial strength and stability of WC P /Fe composites. [ABSTRACT FROM AUTHOR]

The evolution of reaction phases formed in diffusion-bonded SiC/Ta–5W/SiC joints was investigated at a joining temperature of 1500–1700 °C for 10–90 min. The effects of bonding temperature and holding time on the phase evolution were found to be directly correlated with the thickness of the interfacial reaction layer when a 100-μm-thick Ta–5W interlayer was used for joining. In the case of a ~7-μm-thick reaction layer, the interfacial phase constitution consisted of a layered SiC/(Ta,W)C/(Ta,W) 5 Si 3 /(Ta,W) 2 Si/(Ta,W) x Si y /Ta–5W structure. In the reaction layer with a thickness of ~11–26 μm, the interfacial structure evolved into SiC/(Ta,W)C/(Ta,W) 5 Si 3 /(Ta,W)C/(Ta,W) x Si y /(Ta,W) 2 Si/(Ta,W) x Si y /Ta–5W, in which an additional (Ta,W)C/(Ta,W) x Si y layer was inserted between (Ta,W) 5 Si 3 and (Ta,W) x Si y owing to the precipitation of carbon from the (Ta,W) 5 Si 3 layer. When the Ta–5W interlayer was fully consumed to form a stable reaction product, namely the equilibrium state, (Ta,W) x Si y and (Ta,W) 2 Si were eventually transformed into (Ta,W) 5 Si 3 , and the final interface structure that was obtained was SiC/(Ta,W)C/(Ta,W) 5 Si 3 /(Ta,W)C/(Ta,W) 5 Si 3 /(Ta,W)C. This achievement will benefit the design, control, and characterization of SiC/metal interfaces. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metal Materials & Engineering is the property of Northwest Institute for Nonferrous Metal Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to obtain high-quality superalloy castings, the wettability and interactions between superalloy melts with various Y contents and SiO 2 -based ceramic cores were investigated at 1823 K. The results indicated that the wettability and interface reactions were affected by the content of Y in the alloy. For the alloys with Y content less than 0.011 wt%, no Y-oxide was found at the interface, but HfO 2 , Al 2 O 3 and ZrO 2 phases were formed, and the wetting angle dropped slightly. However, different Y-oxides precipitated at the alloy-ceramic interface for the alloys with Y content more than 0.017 wt%, and the wetting angle dropped sharply. When the content of Y was 0.017 and 0.025 wt%, Al 2 O 3 , Y 3 Al 2 (AlO 4) 3 , HfO 2 and ZrO 2 phases were formed at the interface. When the content of Y was 0.1 wt%, YAlO 3 , Y 3 Al 5 O 12 , Y 4 Al 2 O 9 , HfO 2 and ZrO 2 phases were formed. The formation of different reaction products was mainly caused by the change of Y activity (a Y) in the alloy. The reaction between Y and SiO 2 could improve the wettability of the system apparently. [ABSTRACT FROM AUTHOR]

Plasma spray-physical vapor deposition (PS-PVD) was used to prepare tri-layer environmental barrier coatings (EBCs) Si/mullite/Yb 2 SiO 5 on SiC f /SiC substrate. Isothermal oxidation tests of EBCs were performed at 1300 ℃ for 1000 h. The thermochemical and thermomechanical interface interaction among EBCs were investigated. The results show that more dense EBCs can be obtained through PS-PVD process, which is attributed to the mixed deposition of liquid/gas states. After isothermal oxidation, many pores were observed in the Yb 2 SiO 5 coating near the interface of Yb 2 SiO 5 /mullite coating, which results from the diffusion of Yb 2 O 3 phase dissociated from Yb 2 SiO 5 into mullite coating at high temperature. In the mullite coating, the Yb 2 O 3 reacted with Al 2 O 3 generating rod-like Yb 3 Al 5 O 12 phase. Additionally, due to the thermal expansion mismatch and high temperature oxidation, cracks were formed at the interfaces of mullite/Si coating. Those interface cracks resulted in buckling in the mullite coating. [ABSTRACT FROM AUTHOR]

In order to propel the application of the developed CuNi-Xwt%Ti active filler metal in AlN brazing and get the universal reactive wetting mechanism between liquid metal and solid ceramic, the reactive wetting behavior and mechanism of AlN ceramic by CuNi-Xwt%Ti active filler metal were investigated. The results indicate that, with the increasing Ti content, surface tension for liquid CuNi-Xwt%Ti filler metal increases at low-temperature interval, but very similar at high-temperature interval, which influence the wetting behavior on AlN ceramic obviously. CuNi/AlN is the typical non-reactive wetting system, the wetting process including rapid wetting stage and stable stage. The wettability is depended on surface tension of the liquid CuNi filler metal completely. However, the wetting process of CuNi-8wt.%Ti/AlN and CuNi-16 wt%Ti/AlN reactive wetting system is composed by three stages, which are rapid wetting stage decided by surface tension, slow wetting stage caused by interfacial reaction and stable stage. For CuNi-8wt.%Ti/AlN and CuNi-16 wt%Ti/AlN reactive wetting system, although the surface tension of liquid filler metal is the only factor to influence the instant wetting angle θ 0 at rapid wetting stage, the reduced free energy caused by interfacial reaction at slow wetting stage plays the decisive role in influencing the final wettability. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metal Materials & Engineering is the property of Northwest Institute for Nonferrous Metal Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Co has been studied extensively by many research groups as an alternative material for underbump metallization, since Co–Sn compounds show better mechanical properties than Cu–Sn compounds. Information on reactive diffusion at the solid/liquid interface is considerably important to form mechanically and electrically reliable solder joints. In the present study, the kinetics of the reactive diffusion between solid Co and liquid Sn was experimentally examined using semiinfinite Co/Sn diffusion couples prepared by an isothermal bonding technique. Isothermal annealing of the diffusion couple was conducted at temperatures in the range of 523 K to 583 K for various times up to 96 h. An intermetallic layer formed at the original Co/Sn interface in the diffusion couple during annealing. One or two intermetallic compounds among α-CoSn3, β-CoSn3, and CoSn2 were identified, depending on the annealing temperature. The total thickness of the intermetallic layer was proportional to a power function of the annealing time. The overall growth rate of the intermetallic layer did not increase with increasing annealing temperature but was dependent on the kind of compound formed at the interface. The overall growth rate at 583 K was much slower than at lower annealing temperatures, since two compounds (CoSn2 and CoSn3) were identified at the interface, while only CoSn3 formed at 523 K to 563 K. This indicates that the interdiffusion coefficient of CoSn2 is much smaller than that of CoSn3. Based on the exponent of the power function and the microstructure evolution at the moving interface, the layer growth of the compounds was controlled by volume diffusion with spheroidal growth. [ABSTRACT FROM AUTHOR]

It was speculated that ZnFe 2 O 4 was primarily responsible for activating n-butene and α-Fe 2 O 3 was used to activate O 2. The oxidative dehydrogenation of n-butene over α-Fe 2 O 3 /ZnFe 2 O 4 appeared to be the interface reaction. • ZnFe 2 O 4 was responsible for activating n-butene, α-Fe 2 O 3 was used to activate O 2. • The reaction rates were well correlated with the apparent pre-exponential factor. • Efficient contact between ZnFe 2 O 4 and α-Fe 2 O 3 may lead to improving activity. • ODH of n-butene over α-Fe 2 O 3 /ZnFe 2 O 4 appeared to be the interface reaction. Iron-based catalysts were one of the most effective catalysts in the oxidative dehydrogenation of n-butene, however, the roles of spinel and α-Fe 2 O 3 in the biphasic catalyst have remained controversial. Herein, we found that biphasic catalyst exhibited much superior catalytic performance compared to each individual component. According to the temperature programmed desorption, XPS and kinetics studies results, it was speculated that ZnFe 2 O 4 was primarily responsible for activating n-butene and α-Fe 2 O 3 was used to activate O 2. Moreover, the key factor for the catalytic activity of the biphasic catalyst were investigated and kinetic studies showed that reaction rates were well correlated with the apparent pre-exponential factor. Therefore, the efficient contact between ZnFe 2 O 4 and α-Fe 2 O 3 may lead to the improvement of the activity. In addition, the reaction mechanism over α-Fe 2 O 3 /ZnFe 2 O 4 was proposed to be the interface reaction based on the catalytic evaluation results of substituting ZnFe 2 O 4 by the redox-inactive ZnAl 2 O 4. [ABSTRACT FROM AUTHOR]

In this work, nitrogen-doped SiO 2 (N-SiO 2) was successfully synthesized to develop an "adsorption-photocatalytic degradation" water purification technology to remove hydrophobic organic contaminants (HOCs). As a representative of HOCs, decabromodiphenylethane (DBDPE) could be efficiently degraded under simulated sunlight after adsorption on the surface of N-SiO 2. Due to the generation of reactive oxygen species (ROS) and silicon-based radicals, the photodegradation rate of DBDPE on water-SiO 2 interface was 1.5-fold higher than that in water. Furthermore, the transformation pathways of DBDPE on N-SiO 2 surface were compared with that in water. Bond breaking and debromination reactions were the common pathways, while hydroxylation and silicon-based substitution reactions were the specific transformation pathways for DBDPE on the surface of N-SiO 2. Density functional theory (DFT) calculation was used to reveal the generation mechanism of silicon-based radicals and determine the rationality of the involvement of silicon-based radicals in DBDPE transformation. The energy barriers of silicon-based substitution reaction were comparable to that of hydroxylation and debromination reactions, which confirmed the plausibility of the generation of silicon-based substitution products. This study provides an efficient method for the disposal of HOCs, which also gives some new insights into the conversion mechanism of organic pollutants mediated by silicon-based radicals. [Display omitted] • DBDPE can be efficiently degraded on the surface of N-doped SiO 2 under sunlight. • Degradation mechanism of DBDPE in water and on water-SiO 2 interface was compared. • The generation mechanism of silicon-based radicals under sunlight was revealed. • The rationality of silicon-based substitution was confirmed by DFT calculation. [ABSTRACT FROM AUTHOR]

Aluminum foam sandwiches (AFS) with AlSi10 foam cores and AISI 316L steel skins are manufactured by an in-situ bonding process. The precursor of the core foam was made with the powder compacted method. The precursor and skins, coupled together, were then heated up to the melting point of the Al alloy. The gas released by the blowing agent formed hydrogen bubbles in the melt. producing the foam. Such a porous structure was kept frozen at room temperature via cooling in cold water. To optimize the process conditions, some foaming experiments have been conducted with different holding times and temperatures. Such manufactured AFS were cut, chemically etched and studied with an optical microscope associated with image analysis software to get information about pores morphology in terms of circularity and equivalent diameter. The interface AlSi10-AISI316L has been characterized by SEM and EDX to investigate the bonding conditions between cores and skins. Finally, the AFS have been polished and etched to analyze the microstructure. Quasi-static compressive tests have been performed on the AFS. Obtained results showed that the interface formed during the foaming can be characterized by the inter-diffusion of alloying elements, as confirmed by the good quality of metallurgical joints.

Copyright of Rare Metal Materials & Engineering is the property of Northwest Institute for Nonferrous Metal Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents the microstructure evolution and corrosion resistance of Fe-18wt.%Cr-1wt.%Mo-3.5wt.%B alloy against molten zinc at 520 °C. The objective of this study is to obtain Fe-B alloy with superior corrosion resistance through microstructure regulation and to reveal the underlying corrosion mechanism. The results show that the metal matrix of as-cast Fe-Cr-B alloys have undergone a transition from α-(Fe, Cr, Ni) solid solution into γ-(Fe, Cr, Ni) solid solution, while the eutectic boride is further refined with the increasing of Ni addition in the steels. The corrosion resistance of the Fe-Cr-B alloys has significantly been enhanced, with an optimal Ni addition at 10 wt%. Thermodynamic calculations and EPMA results show that Ni mainly exists in the matrix, leading to the transformation of the matrix structure. The improvement of corrosion performance can be attributed to two factors: the refined boride network in Ni-modified Fe-Cr-B alloy act as a barrier for Fe/Zn reaction, and the formation of face-centered cubic (fcc) structure also contributed to improve corrosion resistance owing to a more densely packed structure compared to body-centered cubic (bcc) structure. In the initial stage of corrosion, the de-alloying of Ni occurs first, which result in the transformation from γ-(Fe, Cr, Ni) to α-(Fe, Cr, Ni). Corrosion mechanism for test alloys in molten zinc may be mainly dominated by the formation and propagation of cracks in the borides. The cracks initiated due to the discrepancy in thermal expansion coefficients between Fe-Zn phases and the borides. Unlabelled Image • Fe-18Cr-1Mo-3.5B alloys with various Ni additions were prepared. • The metal matrix transforms from α-Fe to γ-Fe with 10 wt.% Ni addition. • Fe-18Cr-10Ni-1Mo-3.5B alloy has the best corrosion resistance in molten zinc. • The fcc structured matrix shows better corrosion resistance in molten zinc. • The fracture of the borides controls the whole corrosion process. [ABSTRACT FROM AUTHOR]

In this paper, the effect of Y content on interface reaction and wettability between a nickel-base single crystal supperalloy melt and ceramic mould were studied by means of sessile drop tests. The microstructural characterization of the alloy-ceramic interface and the elemental compositions of reaction products were performed by scanning electron microscope (SEM) and electron probe micro-analyzer (EPMA), the phases of reaction products were identified by X-ray diffraction (XRD), and the surface analysis of reaction products was carried out by X-ray photoelectron spectroscopy (XPS). The results showed that Al and Hf in the alloy reacted with SiO 2 in the ceramic mould when Y content was lower than 0.011 wt%, and the reaction products were Al 2 O 3 and HfO 2 , with little change in the wetting angle. However, when Y content was higher than 0.017 wt%, Y and Al in the alloy reacted with SiO 2 in the ceramic mould, and the wetting angle decreased significantly. 0.017 wt% was the critical concentration of Y content that would cause interface reactions. The reaction products of 0.017 and 0.025 wt% Y alloys were Y 3 Al 2 (AlO 4) 3 , the reaction products of 0.1 wt% Y alloy were Y 3 Al 5 O 12 and Y 4 Al 2 O 9 , and the reaction products of 0.5 and 1.0 wt% Y alloys were double reaction layer composed of Y 2 O 3 and Y 3 Al 5 O 12. Si generated by the interface reactions could react with O 2 in the atmosphere to form SiO x during the cooling of the alloy-ceramic couples. • Y-containing interface reactions can obviously increase the wettability. • Al 2 O 3 and HfO 2 are formed at the interface when Y content is less than 0.011 wt%. • Different yttrium aluminate oxides are formed when Y content exceeds 0.017 wt%. • Si generated reacts with O 2 in the atmosphere to form SiO x during the cooling. [ABSTRACT FROM AUTHOR]

Abstract Polymer composite materials are used increasingly in material and engineering science. They provide outstanding mechanical and optical properties. The linkage between the polymer materials is crucial for achieving the desired properties. Understanding the linkage and structure of the polymer-polymer interface layer is a key for utilization polymer composite materials as well as for their fabrication. When analyzing the thin polymer-polymer interface it is important to achieve clear identification of molecular linker structures. One reliable analytical technique allowing this is surface enhanced Raman scattering (SERS) spectroscopy. This study aims at the in-situ evaluation of SERS spectra recorded from the Polycarbonate (PC) –Octadecylamine (ODA) interface to identify the formation of urethane bonds. The detailed analysis of SERS spectra taken before and after the chemical linkage reaction reveals the formation of urethane structures, indicating a chemical bond between PC and ODA. The spectral pattern of urethane groups was identified and evaluated by a reference Raman spectrum. Graphical abstract Image 1 Highlights • Nondestructive in-situ characterization of polymer interphase by SERS. • Silver nanoparticles located at the polymer interface. • Evaluation of molecular interphase structure between Polycarbonate-Octadecylamine. • Formation of an initial urethane linkage. [ABSTRACT FROM AUTHOR]

Abstract Synthetic diamond has excellent mechanical, thermal, and electrical properties, which makes it an ideal material in a wide range applications from abrasive grinding tools to modern electronic devices. Hence, understanding the wettability of metals on the synthetic diamond is of great importance for the development of diamond-related materials and devices. In this study, the wettability and spreading kinetics of binary Sn Cr alloy on chemical vapour deposed (CVD) polycrystalline diamond compacts were investigated using a sessile drop method. In situ observation of contact angle at elevating temperatures indicated trace addition of Cr dramatically improved the wettability of Sn on CVD diamond, and the Sn Cr alloy started to wet CVD diamond at approximately 750 °C. Isothermal spreading kinetic analysis revealed that the spreading of Sn Cr alloy on CVD diamond was controlled by the kinetics of chemical reaction at advancing triple line. Microstructure characterization indicated that the formation of nano-sized scallop-like Cr 7 C 3 grains was responsible for the improved wettability of Sn Cr alloy on CVD diamond substrate. The wetting temperature was found to play a determinant role in the interfacial carbide formation, and hence the reactive wetting of Sn Cr alloy on CVD diamond at temperatures from 700 to 900 °C. Graphical abstract Unlabelled Image Highlights • Small amount of Cr initiates the reactive wetting of Sn on CVD diamond at 750 °C. • Wettability and spreading kinetics of Sn Cr alloys are very sensitive to temperature. • Spreading of Sn Cr alloy is controlled by the chemical reaction kinetics during isothermal wetting. • Formation of nano-sized Cr 7 C 3 carbide improves the wettability of Sn Cr alloy on CVD diamond. [ABSTRACT FROM AUTHOR]

In this paper, thermodynamic calculation and different binary slag interface reaction experiments are used to study the reaction characteristics of different binary slag. The differences in melting process, wetting and reaction behavior were studied. The wetting angle of acidic slag is higher than that the corresponding basic slag. The variation of wetting angle between different binary slag is relatively small. The variation range is only 18 °C. In the melting and reaction process of different binary slag interfaces, the permeation and reaction of the CaO - MgO and CaO - SiO2 interfaces are relatively sufficient. However, there is no obvious chemical reaction between CaO - Al2O3 and Al2O3 - MgO, and the composition and interface separation among each component are more obvious. [ABSTRACT FROM AUTHOR]