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As Fenton reagents, Fe-based amorphous alloys have achieved good results in the treatment of dye wastewater. However, it is rarely reported how to exert the high activity and high adsorption capacity of those amorphous alloys to treat the oily wastewater with more complex components. In this article, Fe78Si8B14 amorphous ribbon was used as the anode and graphite as the cathode to degrade a kind of emulsified oil wastewater by the electro-Fenton (EF) method. The catalytic degradation under such processing parameters as current density, pH values, and H2O2 concentration was investigated. The catalytic performance of the Fe-Si-B amorphous ribbon was characterized by using the degradation efficiency of the emulsified oil wastewater. The water samples before and after degradation by Fe-Si-B amorphous ribbons were examined by infrared spectrophotometry and gas chromatography-mass spectrometer (GC-MS), respectively. The results show that the degradation efficiency of 99.91% is obtained under optimum process conditions of the current density of 30 mA/cm2, pH value of 3, and H2O2 concentration of 20 g/L. Furthermore, all the long-chain organic compounds in the emulsified oil wastewater are decomposed into short-chain organic substances within 40 min of the reaction. Therefore, the EF method with amorphous alloy as anode and graphite as cathode has a good prospect for the degradation of emulsified oil wastewater. Moreover, the obtained results provide a theoretical basis and guidance for the application of amorphous alloy catalysts in practical wastewater remediation applications. [ABSTRACT FROM AUTHOR]

Fe-based amorphous/nanocrystalline alloys exhibit excellent soft magnetic properties, including high saturation magnetic flux density (Bs), high permeability, low coercivity (Hc), and low magnetostriction. They are utilized in distribution transformers, transformers, reactors, and other devices. As green, energy-saving, and environmentally friendly materials, their application fields have more possibilities. In this paper, the development history, composition design principle, heat treatment process, magnetic properties, and annealing brittleness of Fe-based amorphous/nanocrystalline alloys are introduced. [ABSTRACT FROM AUTHOR]

With the wide application of lead acid battery, spent lead acid battery has become a serious problem to environmental protection and human health. Though spent battery can be a contaminant if not handled properly, it is also an important resource to obtain refined lead. Nowadays, the Sb-content in lead storage batteries is about 0.5–3 wt%, which is higher than the Sb-content in the crude lead. However, there are few reports about the process of removing antimony from high-antimony lead bullion. In this study, vacuum displacement reaction technology, a new process for removing antimony from high-antimony lead melts, was investigated. During this process, lead oxide was added to the system and antimony from lead melts was converted into antimony trioxide, which easily was evaporated under vacuum so that antimony was removed from lead melts. The experimental results demonstrated that Sb-content in lead melts decreased from 2.5% to 23 ppm under following conditions: mass ratio of PbO/lead bullion of 0.33, residual gas pressure of 30 Pa, melt temperature of 840 °C, reaction time of 60 min. The distillate gotten can be used as by-product to produce antimony white. Moreover, this study is of importance to recycling of waste lead storage batteries alloy. [ABSTRACT FROM AUTHOR]

Up to now, separating Pb-Sb alloy obtained from jamesonite by conventional pyrometallurgy processes has many drawbacks such as long technological process, high energy consumption, and unsatisfactory separation efficiency. Thinking about the facts that antimony is used mainly in the form of Sb 2 O 3 , and separation of Sb 2 O 3 with good volatility from the lead melt is very easy under vacuum, vacuum dynamic oxidation process, a new and effective process for separating lead and antimony from Pb-Sb alloy, was developed in this work. Experimental results revealed that the content of antimony in Pb-Sb alloy decreased from 42% to 0.30%, that the removal percent of antimony reached 99.59%, and that the PbO content in the distillate was 0.12% under melt temperature of 953 K, vacuum treatment time of 210 min, and air flow rate of 3 L/min, corresponding to the system pressure of 14 kPa. This study is of significance for separating Pb-Sb alloy obtained from jamesonite. [ABSTRACT FROM AUTHOR]

We report a new (Fe (1 − x ) Ni x ) 78 Si 4 B 13 P 5 ( x = 0–0.8) alloys with high AFA and stability of super cooled liquid region. By tuning the ratio of Fe and Ni based on the Fe 78 Si 4 B 13 P 5 alloys, these alloys exhibit tunable and attractive performance is obtained, containing tunable B s of 0–1.57 T, low H c of 2.1–0.7 A/m, high μ e of 9–25 × 10 3 and obviously improved anti-corrosion which meets the requirement of most electric devices. These alloys with similar manufacturability are promising candidates for the application as soft-magnetic materials in electric devices and brazing materials. [ABSTRACT FROM AUTHOR]

Oxidation behaviors of Fe 78 B 13 Si 9 − x P x ( x = 0, 1, 3, 5 and 7) amorphous ribbons were investigated and a refreshing method by annealing in reductive atmosphere were successfully developed by considering the changes of magnetic properties and P content. It is found that the amorphous ribbons with high P content are prone to be oxidized at the beginning of a traditional annealing process. When the annealing process was under reductive atmosphere, however, not only the oxidation can be avoided but also the oxidized ribbon can be refreshed. It is found that, although the color is changed, the amorphous structure for both the oxidized and refreshed ribbons is not changed with the annealing conditions. The refreshing can recover the excellent soft magnetic properties of the alloys with P content lower than 5 at.%. The magnetization process characterized by magnetic domains has revealed the effect of refreshing ability to the oxidized ribbon. It is further confirmed that the refreshing mechanism of the oxidized layer is the valence state change of iron ions from high to low through the seriously oxidized Fe 78 Si 2 B 13 P 7 amorphous ribbon. [ABSTRACT FROM AUTHOR]

We introduce a method for finely adjusting the etch depth profile by dynamic shielding in the course of ion beam etching (IBE), which is crucial for the ultra-precision fabrication of large optics. We study the physical process of dynamic shielding and propose a parametric modeling method to quantitatively analyze the shielding effect on etch depths, or rather the shielding rate, where a piecewise Gaussian model is adopted to fit the shielding rate profile. Two experiments were conducted. The experimental result of parametric modeling of shielding rate profiles shows that the shielding rate profile is significantly influenced by the rotary angle of the leaf. The result of the experiment on fine-tuning the etch depth profile shows good agreement with the simulated result, which preliminarily verifies the feasibility of our method. [ABSTRACT FROM AUTHOR]

Structure effects of distributed feedback (DFB) gratings on lasing action have been investigated for detecting explosive vapors. For the first time, we have established the optimized profiles of the DFB grating, and given the theoretical path to design its structure for amplified spontaneous emission (ASE) of organic polymer films based on Bragg conditions. A poly(p-phenylene ethynylene) (PPE) film can realize detection of dinitrotoluene (DNT) vapors in 2 min with a reduced excitation threshold of 26 mJ cm−2 by using a simple and common 405 nm laser. [ABSTRACT FROM AUTHOR]

This paper introduces a new scheme of ion beam figuring (IBF), or rather variable-spot IBF, which is conducted at a constant scanning velocity with variable-spot ion beam collimated by a variable diaphragm. It aims at improving the reachability and adaptation of the figuring process within the limits of machine dynamics by varying the ion beam spot size instead of the scanning velocity. In contrast to the dwell time algorithm in the conventional IBF, the variable-spot IBF adopts a new algorithm, which consists of the scan path programming and the trajectory optimization using pattern search. In this algorithm, instead of the dwell time, a new concept, integral etching time, is proposed to interpret the process of variable-spot IBF. We conducted simulations to verify its feasibility and practicality. The simulation results indicate the variable-spot IBF is a promising alternative to the conventional approach. [ABSTRACT FROM AUTHOR]

To avoid the influence of fluorine on the extraction of beryllium, separating fluorine from high-fluorine beryllium ore was discussed in this study. The factors affecting on fluorine removal, such as roasting temperature, roasting time, dosage of the additive in roasting process, and the variety and concentration of acid in the leaching process, were separately investigated. The intermediates and final products were identified by XRD. Under the following roasting and leaching conditions: heating temperature 800 °C, treatment time 120 min, additive dosage of Na 2 CO 3 by 60% weight, leaching by distilled water at 50 °C for 30 min and acid (1.7 mol/L HNO 3 ) at 60 °C for 60 min, the percentage of fluorine and beryllium oxide was 1.6%; heating temperature 800 °C, treatment time 180 min, additive dosage of Na 3 PO 4 by 50% weight, leaching by distilled water at 50 °C for 30 min and acid (1.7 mol/L HNO 3 ) at 60 °C for 60 min, the percentage of fluorine and beryllium oxide was 7.12%. Both of the results with additive Na 2 CO 3 and Na 3 PO 4 can meet the requirement of the industrial production of beryllium after the pretreatment, while Na 2 CO 3 is more efficient. Results also indicated that nitric acid was more reactive than sulfuric acid. [ABSTRACT FROM AUTHOR]

The conventional pyrometallurgical method for separating lead–antimony alloy produced from jamesonite has a lot of imperfections such as long-term process, tremendous energy cost and harm to the environment. Therefore, a new method to separate lead and antimony from lead–antimony alloy by fractional crystallization is investigated. The experimental results demonstrate that the lead content decreases with the increase of length to the metal column’s bottom. Lead content of the bottom can reach larger than 80% by weight after lifting. In the experimental speed range, the lifting speed has very small impact on the separation effect. After 4 times’ lifting, crude lead bullion (larger than 83% by weight) whose lead content is close to the eutectic point of lead–antimony binary system is gained in the bottom and the antimony can be used for further refining process without converting into Sb 2 O 3 . The separating efficiency of lead in the bottom has reached the theoretical level of fractional crystallization for lead–antimony alloy containing about 40% by weight antimony. [ABSTRACT FROM AUTHOR]

Lead sulfate, lead oxides and lead metal are the main component of lead paste in spent lead acid battery. When lead sulfate was desulfurized and transformed into lead carbonate by sodium carbonate, lead metal and lead oxides remained unchanged. Lead carbonate is easily decomposed to lead oxide and carbon dioxide under high temperature. Namely, vacuum thermal process is the reduction reaction of lead oxides. A compatible environmental process consisted of hydrometallurgical desulfurization and vacuum thermal reduction to recycle lead was investigated in this research. Lead paste was firstly desulfurized with sodium carbonate, by which, the content of sulfur declined from 7.87% to 0.26%. Then, the desulfurized lead paste was reduced by charcoal under vacuum. Under the optimized reaction conditions, i.e., vacuum thermal reduction at temperature 850 °C under 20 Pa for 45 min, a 22.11 × 10 −2 g cm −2 min −1 reduction rate, and a 98.13% direct recovery ratio of fine lead (99.77%) had been achieved, respectively. [ABSTRACT FROM AUTHOR]

Vacuum co-pyrolysis of Chinese fir sawdust (CFS) and waste printed circuit boards (WPCBs) at different heating conditions were examined in this paper. The composition of the pyrolysis oils was analyzed by gas chromatography–mass spectrometry (GC–MS). It was found that the content of most of the compounds with relatively long molecular chain had a higher value at relatively low temperature (400–600 °C) and short holding time (10 min), and decreased at relatively high temperature (800 °C) and long holding time (30–90 min); while the content of most of the compounds with relatively short molecular chain presented an adverse trend. The co-pyrolysis process was also analyzed by thermogravimetric (TG) analysis with evolved product analysis by Fourier transform infrared (FTIR) spectroscopy. The results showed that the volatiles were mainly generated between 300 and 500 °C, and after 500 °C, noncondensable gases (CO 2 , CO and CH 4 ) were the main components in the pyrolysis process. [ABSTRACT FROM AUTHOR]

Abstract: Separation and recovery process of zinc from scrap copper-based alloy was carried out under vacuum condition in a sublimation reactor. The factors affecting the evaporation ratio of copper-based alloy and the separation efficiency of zinc, such as heating temperature, residual gas pressure, vacuum evaporation time and the amount of scrap copper-based alloy were separately investigated. The experimental results revealed that zinc was successfully separated from the scrap copper-based alloy, where the evaporation ratio of copper-based alloy reached 18.43%. Namely, 96.09% by weight of zinc could be removed under the condition: residual gas pressure of 50 Pa, heating temperature of 1323 K and vacuum evaporation time of 90 min. If corresponding to the residual gas pressure 500 Pa, the evaporation ratio reached 18.17%, and 94.73% by weight of zinc could be removed under the following experimental conditions: temperature 1323 K, vacuum evaporation time 180 min. Meanwhile, the thermodynamics of vacuum sublimation and refining to recover zinc was analyzed and calculated. [Copyright &y& Elsevier]

Highlights: [•] Co-pyrolysis process presents antagonistic effect in the yields of the volatiles. [•] Co-pyrolysis process is good for the formation of brominated aromatic compounds. [•] The volatiles were mainly formed between 300 and 450°C in the pyrolysis process. [•] Noncondensable gases (CO2, CO, CH4, etc.) were the main components after 450°C. [•] Co-pyrolysis oils show better synthetic properties than the separate ones. [ABSTRACT FROM AUTHOR]

Abstract: Spent lithium-ion batteries containing lots of strategic resources such as cobalt and lithium are considered as an attractive secondary resource. In this work, an environmentally compatible process based on vacuum pyrolysis, oxalate leaching and precipitation is applied to recover cobalt and lithium from spent lithium-ion batteries. Oxalate is introduced as leaching reagent meanwhile as precipitant which leaches and precipitates cobalt from LiCoO2 and CoO directly as CoC2O4·2H2O with 1.0M oxalate solution at 80°C and solid/liquid ratio of 50gL−1 for 120min. The reaction efficiency of more than 98% of LiCoO2 can be achieved and cobalt and lithium can also be separated efficiently during the hydrometallurgical process. The combined process is simple and adequate for the recovery of valuable metals from spent lithium-ion batteries. [Copyright &y& Elsevier]

Abstract: In crude lead or copper electrorefining, the by-product anode slime is an important material of recycling precious metals. However, the existing methods for treating arsenic-rich anode slime are less than satisfactory not only for the removal effect of arsenic but also for the environment protection. Therefore, a new technology for treating arsenic-rich anode slime was proposed in this paper, namely the two-step process of vacuum dynamic evaporation (VDE) and vacuum dynamic flash reduction (VDFR). Through this two-step process, silver from the anode slime was left behind in distilland as the silver alloy, and the trivalent oxide of arsenic was evaporated in the distillate. The experimental results showed that the removal ratio of arsenic was 99.96%. Moreover, these vacuum technologies offer improvements in metallurgical and environmental performance. [Copyright &y& Elsevier]

Abstract: Spent lithium-ion batteries contain lots of strategic resources such as cobalt and lithium together with other hazardous materials, which are considered as an attractive secondary resource and environmental contaminant. In this work, a novel process involving vacuum pyrolysis and hydrometallurgical technique was developed for the combined recovery of cobalt and lithium from spent lithium-ion batteries. The results of vacuum pyrolysis of cathode material showed that the cathode powder composing of LiCoO2 and CoO peeled completely from aluminum foils under the following experimental conditions: temperature of 600°C, vacuum evaporation time of 30min, and residual gas pressure of 1.0kPa. Over 99% of cobalt and lithium could be recovered from peeled cobalt lithium oxides with 2M sulfuric acid leaching solution at 80°C and solid/liquid ratio of 50gL−1 for 60min. This technology offers an efficient way to recycle valuable materials from spent lithium-ion batteries, and it is feasible to scale up and help to reduce the environmental pollution of spent lithium-ion batteries. [Copyright &y& Elsevier]

Abstract: Waste lead storage battery is the most important recyclable lead material not only in various European and other OECD countries but also in China. Pollution control of lead has become the focus of people’s attention in the world. A vacuum process for recycling waste lead storage battery was developed in this work. The experimental results showed that all the valuable materials in waste lead storage battery could be satisfactorily recycled by vacuum technologies. The vacuum melting of lead grids and the vacuum reduction of lead pastes produce the lead bullion with the direct recovery ratio of 96.29% and 98.98%, respectively. The vacuum pyrolysis of plastics can produce pyrolysis oil with yield of more than 93 wt.%. These vacuum recycling technologies offer improvements in metallurgical and environmental performance. [Copyright &y& Elsevier]

Abstract: Activated carbons with high surface area, large pore volume, and high mesoporosity were prepared from herb residues. The raw material was treated by 0.5M NaOH solution and activated under vacuum using ZnCl2 as the activation agent. Four activated carbons obtained under different preparation conditions were compared in detail. It was found that both the vacuum condition and base-leaching process have positive effects on the specific surface area and mesopore structure characteristics. The Brunauer–Emmett–Teller (BET) surface area and total pore volume of the activated carbon obtained by combining vacuum condition and base-leaching method have increased by 125.3% and 64.9% respectively comparing with those of activated carbon prepared under atmosphere without base-leaching. With an activation temperature of 450°C and an impregnation ratio of 2.5, activated carbon with a BET surface area of 1952m2/g, a total pore volume of 1.479cm3/g, and a mesoporosity of 98.0% was obtained. The thermal decomposition properties of raw materials and activated carbons were studied. Furthermore, the effects of preparation parameters such as activation temperature and impregnation ratio on the properties of activated carbons were investigated. The scanning electron microscopy images of the activated carbon showed a porous structure. [Copyright &y& Elsevier]

Abstract: Activated carbons were prepared from walnut shells by vacuum chemical activation with zinc chloride as the activation agent. To optimize the preparation method, the effects of the main process parameters (such as system pressure, activation temperature, and impregnation ratio) on the properties (expressed in terms of specific surface area and pore volume) of the obtained activated carbons were studied. It was found that the optimum activated carbon obtained with system pressure of 30kPa, activation temperature of 450°C, and impregnation ratio of 2.0 has a BET surface area of 1800m2/g and total pore volume of 1.176cm3/g. The prepared activated carbons were characterized by SEM, TEM, and FTIR. Then they were used as an adsorbent for the removal of methylene blue from aqueous solutions. The results showed that the methylene blue adsorption capacity was positively correlated to the BET surface area. The highest methylene blue adsorption capacity was 315mg/g for the optimum activated carbon. The effect of the dose of the activated carbon was evaluated and the adsorption isotherm of methylene blue was determined. Redlich–Peterson and Langmuir–Freundlich models were found to best represent the equilibrium data, suggesting heterogeneous surface adsorption of methylene blue on the activated carbon. [Copyright &y& Elsevier]

Abstract: Waste printed circuit boards (WPCBs) contain lots of valuable resources together with plenty of hazardous materials, which are considered both an attractive secondary resource and an environmental contaminant. In this research, a new process of “centrifugal separation+vacuum pyrolysis” for the combined recovery of solder and organic materials from WPCBs was investigated. The results of centrifugal separation indicated that the separation of solder from WPCBs was complete when WPCBs were heated at 240°C, and the rotating drum was rotated at 1400rpm for 6min intermittently. The results of vacuum pyrolysis showed that the type-A of WPCBs without solder pyrolysed to form an average of 69.5wt% residue, 27.8wt% oil, and 2.7wt% gas; and pyrolysis of the type-B of WPCBs without solder led to an average mass balance of 75.7wt% residue, 20.0wt% oil, and 4.3wt% gas. The pyrolysis residues contain various metals, glass fibers and other inorganic materials, which could be recycled for further processing. The pyrolysis oils can be used for fuel or chemical feedstock and the pyrolysis gases can be collected and combusted for the pyrolysis self-sustain. This clean and non-polluting technology offers a new way to recycle valuable materials from WPCBs and prevent the environmental pollution of WPCBs effectively. [Copyright &y& Elsevier]

Thermophotovoltaic (TPV) systems consume near infrared (NIR) filters, which are key components for high conversion efficiency. Bandpass filters employing annular aperture array (AAA) on a fused silica substrate are one of candidates for matching GaSb cells in high-temperature TPV. It is often placed independently between the emitter and cell, and thus spectral control and heat insulation are simultaneously realized. For high efficiency, the smaller the characteristic size and the larger the size is beneficial for the filter. Novel sidewall lithography based on conventional interference lithography and ion-beam etching is first proposed and used for cost-effective fabrication. An AAA filter with a 80 nm critical dimension in a 100 mm × 160 mm area has been fabricated successfully. After the annealing process at 500 °C, the peak transmittance is increased to 70% from 65%, and no deformation is observed in the structural parameters of the filter before and after annealing, and calculated results demonstrate that the spectral efficiency is about 61%. [ABSTRACT FROM AUTHOR]

Post-bond heat treatment (PBHT) is an effective way to improve the bonding quality of a brazed joint. Herein, brazing of a nickel-based single crystal superalloy is carried out using a Ni-Cr-Co-B-Si-Al-Ti-W-Mo filler alloy, and the microstructure and creep property of the brazed joint are systematically investigated using scanning electron microscopy (SEM), Thermo-Calc software, an electron probe micro-analyzer (EPMA), X-ray diffractometer, confocal scanning laser microscope (CSLM), and transmission electron microscopy (TEM). The results reveal that the as-prepared joint only consists of an isothermally solidified zone (ISZ) and an athermally solidified zone (ASZ), where the cubic γ′ phase is observed in the ISZ, and skeleton-like M3B2, γ + γ′ eutectic and reticular G phases are observed in the ASZ. Furthermore, the γ + γ′ eutectic and G phases disappear and the M3B2 alters from a skeleton-like to block-like shape in the ASZ after PBHT. Meanwhile, some lath-like M3B2 phases are precipitated at the edge of the ISZ and several M3B2 phases are precipitated in the base metal, forming a new zone in the brazed joint, namely at the diffusion affected zone (DAZ). Owing to the removal of low melting point eutectics from the as-prepared joint, the creep life also increases from 188 h to 243 h after PBHT. The current work provides a method for the optimization of brazed joints based on the Ni-based single crystal superalloy. [ABSTRACT FROM AUTHOR]

Microalloying is an effective method to improve the mechanical properties of 6063 Al–Mg–Si alloy. Here, in this work, the effects of trace Cu (0.14 wt.%) and Cr (0.10 wt.%.) additions on the microstructure and mechanical properties of 6063 Al–Mg–Si alloy were studied. The results show that the additions of two elements can cause significant age-hardening effects, and the yield and tensile strengths of the alloys are significantly increased after T6 heat treatment. Further, it is found that the Cu and Cr additions show different strengthening mechanisms in the alloy. Cu addition leads to a finer and denser distribution of the main strengthening phases in the peak aging of the alloy, as well as a large number density of the precipitated phases, resulting in an increase in the dislocation density of the alloy during strain and hindering the dislocation movement. However, Cr addition acts as an inhibitor of grain growth and results in grain refinement, which also increases the hindrance of dislocation movement during the plastic deformation of the alloy, resulting in an increase in the dislocation density, thereby strengthening the alloy. [ABSTRACT FROM AUTHOR]

• A novel technology, for atomic economic recovery of lead paste, is proposed. • Direct recovery ratio of Pb reaches 99.29%, which means that Pb-loss is very little. • Sb-content in crude Pb-Sb alloy decreased from 46% to 0.98%. • The technology has advantages of lower cost and less pollution, etc. Until today, there are still many problems that must be solved through innovative research to make the recycling of spent lead-acid batteries and the separation of Pb-Sb alloy more environmentally friendly and energy-saving. In this paper, a novel method for regenerating lead paste, by vacuum reduction reaction coupling with separation of Pb-Sb alloy, was developed. In this process, antimony from Pb-Sb alloy is used to reduce desulfurized lead paste into lead under vacuum, while it is oxidized into volatile Sb 2 O 3 as by-product. The results showed that direct recovery ratio of Pb from desulfurized lead paste reached 99.29% and Sb-content in Pb-Sb alloy decreased from 46% to 0.98% under following conditions: the mass ratio of desulfurized lead paste to Pb-Sb alloy of 1.50, residual gas pressure of 30 Pa, reduction temperature of 810 °C for 50 min. By this method, not only the lead paste can be recovered with high atom economy, but also the Pb-Sb alloy can be separated efficiently at zero cost and without "three wastes" generation. Therefore, this method is very useful for the recycling of spent lead-acid battery and the separation of Pb-Sb alloy. [ABSTRACT FROM AUTHOR]

The effect of doping ceramic reinforcing particles during the fabrication of amorphous alloy coatings by laser cladding technology has rarely been investigated. A crack-free Fe-based amorphous/crystalline composite coating with good tribological properties was prepared on the surface of 40Cr steel by changing the content of WC–14Co addition during laser cladding. As the content of WC–14Co particles increases, cracks in the coating are first suppressed until gradually disappearing and then re-forming, reaching a crack-free state at 5 wt% addition. SEM, TEM and EBSD results showed that the incorporation of WC–14Co successfully introduced fine WC particles into the coating structure and refined the microstructure of the coating. The Vickers hardness of the coating is 937.7 Hv, and the wear loss of the coating was 1.1 × 10–2 mm3 at a load of 30 N, a friction counterpart of Al2O3, and a sliding speed of 9 mm/s for 1.5 h. The crack-free and good tribological properties of the coating were mainly attribute to the uniform and diffuse distribution of WC, which inhibits the directional growth of columnar crystals at the coating–substrate interface and promotes the refinement of the crystal structure. [ABSTRACT FROM AUTHOR]

Fe‐based amorphous and nanocrystalline alloys are widely used in transformers, electronic information, and aerospace applications due to their high saturation flux density (Bs), high permeability, low iron loss, and low coercivity (Hc). This article briefly introduces soft magnetic materials, gives an overview of the classification, preparation methods, soft magnetic properties, and applications of Fe‐based amorphous and nanocrystalline alloys, and reviews the effects of elements such as Fe, Co, Ni, Si, B, P, and Nb in the alloys on the properties of Fe‐based amorphous and nanocrystalline alloys such as amorphous forming ability, Bs and Hc. The challenges and development directions of Fe‐based amorphous and nanocrystalline alloys in research are pointed out. [ABSTRACT FROM AUTHOR]

Conventional detinning process of lead bullion usually includes the following problems: the oxidizing refining process takes a long time to finish the oxidation of tin and products mass slag, while the basic refining process consumes large reagent, and the labor condition is poor. Therefore, a novel technique with oxygen controlled under vacuum condition for removing tin in crude lead was investigated, which shows characters such as, low-energy consumption, less metal wastage and environmental friendly. During this process, tin was removed from lead bullion by converting to tin oxide and concentrating in the dross. The experimental results showed that the residual Sn-concentration in detinned lead was about 2 ppm corresponding to the lead loss ratio about 2–3 wt% under the following experimental conditions: temperature of 750 °C, oxidation time of 80 min, agitation speed of 100 rpm and air flow rate of 60 mL/min corresponding to the residual gas pressure of 57 KPa. [ABSTRACT FROM AUTHOR]

In order to gain insight into how the addition of Cu element affects the crystallization mechanism of amorphous nanocrystalline alloys and soft magnetic properties, the crystallization behavior of (Fe 0.83 B 0.11 Si 0.02 P 0.03 C 0.01) 100-x Cu x (x = 0 and 0.5) amorphous ribbons was investigated based on kinetic and thermodynamic behavior under non-isothermal and isothermal annealing conditions. The results show that under non-isothermal annealing conditions, the Cu0.5 amorphous ribbon not only favors the formation of the amorphous structure, but also enlarges the temperature window for annealing and improves the thermal stability of the α-Fe(Si) phase. At the same time, the Cu0.5 amorphous ribbon shows slow kinetic and is insensitive to heating rate change during annealing treatment. Under isothermal conditions, the addition of Cu decreases the nucleation activation energy (E n) and increases the growth activation energy (E g). This further indicates that the nucleation of α-Fe(Si) grains is easier than the growth process, which is conducive to the formation of a homogeneous nanostructure and improves the soft magnetic properties of the alloy. Compared to Cu0 amorphous ribbon, it is also shown that the Cu0.5 amorphous ribbon changes the crystallization mechanism from diffusion-controlled one-dimensional to two-dimensional growth when the crystallization volume fraction x is 10–30 vol%. While three-dimensional growth become dominated when x is reaches 60 vol% for both ribbons. Therefore, the kinetics of crystallization as well as microstructure supports that the Cu0.5 ribbon is able to exhibit uniformly fine nanocrystalline structures. Further, the Cu0.5 nanocrystalline ribbon shows a higher B s of 1.85 T and a lower H c of 2.55 A/m, respectively, and the favorable (100) orientation of α-Fe(Si) grains formed after annealing is another factor to increase B s. • The Cu-containing alloy show kinetic insensitivity and is suitable for a high heating rate. • The addition of Cu changes the crystallization mechanism when x is between 10% and 30%. • When the applied magnetic field is ND, precipitation of (100) orientation α-Fe grains favors enhancing B s. • The Cu0.5 alloy show B s of 1.85 T, H c of 2.55 A/m. [ABSTRACT FROM AUTHOR]

Sn60Pb40 alloy powders were fabricated using the planar flow casting (PFC) atomization process. By using OM, SEM and EPMA, the characteristics of the morphologies and microstructures of the powders have been investigated. It is observed that the environment of ambient gas in the atomization box has great effects on the morphology of the alloy powders. The microstructures of Sn60Pb40 alloy powders produced by the PFC atomization process are completely composed of eutectic, which is made up of both oversaturated α solid solution and β solid solution. The microstructures of small size powders are extraordinarily undeveloped dendritic eutectic, in which the large majority of the α phase appears nearly spherical, evidently since the cooling rate is higher and the under-cooling is larger. As for the large size powders, since the cooling rate and undercooling are relatively low, lamellar α phase apparently increases in the eutectic microstructures of these powders, and there is even typical lamellar eutectic structure clearly observed in some micro-areas. After remelting tests by DTA, the microstructures of small size powders are transformed, which become composed of large crumby α phase and eutectic (α+β), while those of large size powders change into classical tin-lead structures of primary α phase plus lamellar eutectic (α+β). By studying the microstructures of tin-lead alloy powders, a model has been proposed to predict the microstructure formation of Sn60Pb40 alloy powders. [ABSTRACT FROM AUTHOR]

In this work, the effects of annealing temperatures and time on the microstructure and soft magnetic properties of (Fe 0.83 B 0.11 Si 0.02 P 0.03 C 0.01) 99.5 Cu 0.5 nanocrystalline alloy were investigated using a new rapid annealing process. The results show that at each annealing temperature, there exists an annealing time for optimum soft magnetic properties. The annealing temperature and time were further optimized, and excellent properties with high saturation magnetic induction B s of 1.79 T and low coercivity H c of 2.7 A/m were obtained by annealing at 431 °C for 150 s. A microstructure consisting of uniform and fine α-Fe(Si) grains with high number density and high crystallization volume fraction was found to be the key to ensure high B s and low H c. However, with increasing annealing time, it was found that α-Fe(Si) grains existed aggregation phenomenon (in the form of high-angle grain boundaries), with the simultaneous precipitation of Fe-B compound precipitated in the residual amorphous matrix. This not only causes the uneven distribution of nanocrystals, but also destroys the competitive effect between nanocrystals and the stability of the structure, thus deteriorating the soft magnetic properties. [ABSTRACT FROM AUTHOR]

The effects of Ni content on the phase constituent, mechanical properties and damping capacity of the AlCrFe 2 Ni x (x = 1.0, 1.5, 1.7, 2.1, 2.2 and 2.3) medium entropy alloys (MEAs) were studied. When x = 2.1, the microstructure of the MEA consists of BCC phase as the matrix and FCC phase as the second phase with the corresponding volume fractions of 87.7, 12.3 vol%, respectively. The combination of hard BCC matrix and soft FCC secondary phase, especially, the BCC phase is isolated by the circular FCC phase, results in a very high damping capacity up to 0.06936 for the AlCrFe 2 Ni 2.1 MEA at the corresponding strain amplitude of 2.55 × 10−4. Both the BCC matrix and the peculiar microstructure play a key role in increasing the damping capacity of the AlCrFe 2 Ni 2.1 MEA. Excellent damping performance and comprehensive tensile properties of AlCrFe 2 Ni 2.1 MEA indicate that it has potential applications as the candidate of damping materials. • The increase of Ni molar ratio of AlCrFe 2 Ni x medium entropy alloys (MEAs) promotes the phase transition tendency from BCC to FCC. • AlCrFe 2 Ni 2.1 MEAs consisted of BCC phase as matrix and FCC phase as secondary phase have outstanding damping capacity. • A circular FCC phase, similar to the grain boundary, is distributed on the BCC matrix of AlCrFe 2 Ni 2.1 medium entropy alloy. • AlCrFe 2 Ni 2.1 MEAs exhibit excellent strength and suitable plastic strain when BCC phase is dominated as the matrix. [ABSTRACT FROM AUTHOR]

• Fe-based amorphous nanocrystalline alloys are studied by molecular dynamics. • The effect of the volume fraction of nanocrystals on the brittleness is investigated. • Classification of samples into three categories based on hardness gradients. • The volume fraction of nanocrystals on brittleness has a critical value. The effect of the volume fraction of body-centered cubic (BCC) crystal in Fe-based amorphous nanocrystalline alloys on room temperature brittleness was investigated via molecular dynamics simulations. Seven model samples with embedded BCC nanocrystal contents ranging from 0 to 33.4 vol.% were obtained. The indentation tests were carried out by spherical rigid indenter to investigate the microstructural evolution and the mechanical properties of those Fe-based amorphous/nanocrystalline alloys in terms of the indentation force, hardness, von Mises shear strain, atomic displacement vector as well as surface morphology. It is found virtually that the plasticity shows a gradient decrease tendency for the three types of samples with 0, less than 16, and more than 20 vol.% nanocrystal, respectively, which is caused by the free volume decreases via monitoring the Voronoi polyhedra. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we demonstrate a new method for fabrication centimetre-long, dense and vertical sidewalls silicon-on-insulator (SOI) mould using holographic method combine with crystallographic anisotropic etching. Holographic method can make narrow dense and multiple continuous lines in large area while crystallographic anisotropic etching could eliminate line-edge-roughness (LER) in sidewalls and make the sidewalls nearly atomic-scale smoothness. Therefore, the line width of the SOI mould will in a high uniformity and the sidewalls will be smooth and vertical over centimetre lengths. Compare to common NIL mould, the smooth and vertical sidewall of SOI mould provided an easier demoulding process after NIL. Multiple centimetre-long fluidic-channels with smooth and vertical sidewall fabricated by faithfully imprint of SU-8 and an optimised sealing process using free-standing SU-8 bonding film. [Copyright &y& Elsevier]

Abstract: Fluorinated reduced graphene oxide (F-RGO) is prepared by CF4 plasma treatment of RGO. The fluorine (F) doping is confirmed by X-ray photoelectron spectroscopy and its content is directly related to the plasma exposure time. A modest p-doping effect of the fluorination is observed from the electrical measurements. It is found that the F-RGO is an even better substrate for surface enhanced Raman spectroscopy of molecules than RGO. The relative enhancement factor can be tuned by manipulating the F content in the F-RGO. The effect is attributed to the presence of the strong local electric field induced by the local dipoles of F-containing groups on the F-RGO surface. This shows that the formation of well-designed surface dipoles could be a general way to increase the chemical enhancement of molecular Raman spectra. [Copyright &y& Elsevier]

Abstract: Here, we focused on the recycling of waste printed circuit boards (WPCBs) using vacuum pyrolysis-centrifugation coupling technology (VPCT) aiming to obtain valuable feedstock and resolve environmental pollution. The two types of WPCBs were pyrolysed at 600°C for 30min under vacuum condition. During the pyrolysis process, the solder of WPCBs was separated and recovered when the temperature range was 400–600°C, and the rotating drum was rotated at 1000rpm for 10min. The type-A of WPCBs pyrolysed to form an average of 67.91wt.% residue, 27.84wt.% oil, and 4.25wt.% gas; and pyrolysis of the type-B of WPCBs led to an average mass balance of 72.22wt.% residue, 21.57wt.% oil, and 6.21wt.% gas. The GC–MS and FT-IR analyses showed that the two pyrolysis oils consisted mainly of phenols and substituted phenols. The pyrolysis oil can be used for fuel or chemical feedstock for further processing. The recovered solder can be recycled directly and it can also be a good resource of lead and tin for refining. The pyrolysis residues contained various metals, glass fibers and other inorganic materials, which could be recovered after further treatment. The pyrolysis gases consisted mainly of CO, CO2, CH4, and H2, which could be collected and recycled. [Copyright &y& Elsevier]

Abstract: In this research, a two-step process consisting of vacuum pyrolysis and vacuum centrifugal separation was employed to treat waste printed circuit boards (WPCBs). Firstly, WPCBs were pyrolysed under vacuum condition at 600°C for 30min in a lab-scale reactor. Then, the obtained pyrolysis residue was heated under vacuum until the solder was melted, and then the molten solder was separated from the pyrolysis residue by the centrifugal force. The results of vacuum pyrolysis showed that the type-A of WPCBs (the base plates of which was made from cellulose paper reinforced phenolic resin) pyrolysed to form an average of 67.97 wt.% residue, 27.73 wt.% oil, and 4.30 wt.% gas; and pyrolysis of the type-B of WPCBs (the base plates of which was made from glass fiber reinforced epoxy resin) led to an average mass balance of 72.20 wt.% residue, 21.45 wt.% oil, and 6.35 wt.% gas. The results of vacuum centrifugal separation showed that the separation of solder was complete when the pyrolysis residue was heated at 400°C, and the rotating drum was rotated at 1200rpm for 10min. The pyrolysis oil and gas can be used as fuel or chemical feedstock after treatment. The pyrolysis residue after solder separation contained various metals, glass fibers and other inorganic materials, which could be recycled for further processing. The recovered solder can be reused directly and it can also be a good resource of lead and tin for refining. [ABSTRACT FROM AUTHOR]

The effect of 1 at. % Cu addition and annealing temperatures on the soft magnetic properties of Fe81B13P3Si2C1 amorphous ribbons was investigated in this paper. The results show that both Fe81B13P3Si2C1 and (Fe81B13P3Si2C1)0.99Cu1 amorphous/nanocrystalline alloys possess excellent soft magnetic properties. Minor Cu addition can enlarge the temperature interval between first and second crystalline temperatures from 48 K to 112 K, enlarging the processing window and increasing the thermal stability of the amorphous alloy. The annealed Fe81B13P3Si2C1 amorphous/nanocrystalline alloy exhibits saturation flux densities (Bs) on the order of 1.69 T and coercivities (Hc) of 14.6 A/m, and the annealed (Fe81B13P3Si2C1)0.99Cu1 alloy shows a high Bs value of up to 1.92 T and Hc of 11.6 A/m. The soft magnetic properties were discussed in terms of microstructure and magnetic domain observation. [ABSTRACT FROM AUTHOR]

By using Zr41.2Ti13.8Ni10Cu12.5Be22.5 (Vit1) bulk metallic glass with a defined cooling history, the heat capacity (Cp) of liquid and glass, and the calorimetric glass transition in differential scanning calorimetry experiments were investigated. Then, a thermal equilibrium model related to the melting and solidifying process was established to extrapolate the solidification glass transition (SGT) temperature range during liquid to glassy solid phase transformation. By using the extrapolated SGT temperature range, the thermodynamic parameters, including the Cp and thermal conductivity (λ), were adjusted, which can make the simulated cooling temperature curves accurately reflect the recorded ones. The coincidence of experimental and simulation results indicates the rationality of the thermal equilibrium model established in the present work. Furthermore, it is proposed that the SGT is resulted from the falling out-of-equilibrium of the undercooled liquid metal that acts as an endothermic trap to suppress the occurrence of recalescence. [ABSTRACT FROM AUTHOR]

We designed and fabricated polarization-independent multilayer dielectric reflection gratings of 1300 line/mm for spectral beam combining. Because the designed grating has a duty cycle (or fill factor) much greater than 0.5, we used the lift-off process to invert a less-than-0.5 duty cycle photoresist mask to a greater-than-0.5 duty cycle chromium mask. Because the simultaneous polarization-independence and high-angular-dispersion requirements greatly reduce fabrication tolerance, we employed the end-point detection techniques to control accurately the duty cycle and groove depth of the grating profile to reach the design target. The measured polarization-averaged diffraction efficiency of the fabricated gratings was greater than 97% in the wavelength range of 1050 nm–1080 nm. [ABSTRACT FROM AUTHOR]

A fabrication method comprising near‐field holography (NFH) with an electron beam lithography (EBL)‐written phase mask was developed to fabricate soft X‐ray varied‐line‐spacing gratings (VLSGs). An EBL‐written phase mask with an area of 52 mm × 30 mm and a central line density greater than 3000 lines mm−1 was used. The introduction of the EBL‐written phase mask substantially simplified the NFH optics for pattern transfer. The characterization of the groove density distribution and diffraction efficiency of the fabricated VLSGs indicates that the EBL–NFH method is feasible and promising for achieving high‐accuracy groove density distributions with corresponding image properties. Vertical stray light is suppressed in the soft X‐ray spectral range. [ABSTRACT FROM AUTHOR]

In this paper, cryogenic treatment (at 77K) was first applied to solve the problem of strength and plasticity balance of body-centered cubic (BCC) type Al 1.4 CrFe 2 Ni 2 high entropy alloy (HEA). The microstructure and mechanical properties of the HEAs after cryogenic treatment was studied systematically. The results show that cryogenic treatment has an intensive effect on the nanophases (B2), dislocations and mechanical properties. The nanophase is refined to 126.05 nm with cryogenic treatment for 24 h, which is 42.7% lower than the matrix alloy. The number of the nanophase is increased by 60%. With the increasing of cryogenic treatment time, the dislocation morphology evolves from short linear shape to long curved shape and ring shape in turn, and the dislocation density increases significantly. Al 1.4 CrFe 2 Ni 2 HEA exhibits excellent mechanical properties (480 HV hardness and 3107 MPa fracture strength) after cryogenic treatment for 24 h, which increase 9.1% and 24.33% than the matrix alloy (440 HV and 2499 MPa) while maintain high fracture strain, up to 40.8%. This is attributed to the volume shrinkage and lattice distortion superposition of HEAs cause the extrusion effect between grains. Under the effect of cryogenic treatment, the internal stress increased with volume shrinkage and the dislocation strengthening obviously. [ABSTRACT FROM AUTHOR]

In this work, we experimentally investigate the surface nano-roughness during the inductively coupled plasma etching of fused silica, and discover a novel bi-stage time evolution of surface nano-morphology. At the beginning, the rms roughness, correlation length and nano-mound dimensions increase linearly and rapidly with etching time. At the second stage, the roughening process slows down dramatically. The switch of evolution stage synchronizes with the morphological change from dual-scale roughness comprising long wavelength underlying surface and superimposed nano-mounds to one scale of nano-mounds. A theoretical model based on surface morphological change is proposed. The key idea is that at the beginning, etched surface is dual-scale, and both larger deposition rate of etch inhibitors and better plasma etching resistance at the surface peaks than surface valleys contribute to the roughness development. After surface morphology transforming into one-scale, the difference of plasma resistance between surface peaks and valleys vanishes, thus the roughening process slows down. [ABSTRACT FROM AUTHOR]

The effect of P on the glass forming ability, soft magnetic properties and oxidation behavior of Fe 78 B 13 Si 9- x P x ( x = 0–7) amorphous alloys were investigated. It is found that the proper introduction of P, can effectively improve the glass forming ability and stability of supercooled liquid region. Fe 78 Si 4 B 13 P 5 BMG, which exhibits high saturation flux density of 1.56 T, was readily made into rod sample with a diameter of 1.5 mm under air casting atmosphere. P bearing alloys also exhibit excellent soft magnetic properties containing low coercivity of 1.7–2.7 A/m, and high effective permeability of 8200–12,200. Slight oxidation can further improve the coercivity to a lower value of 1.1 A/m and the higher effective permeability to 11,900 for the alloys with P content no more than 3 at. %. Excessive addition of P may deteriorate the glass forming ability, soft magnetic properties and oxidation behavior. Magnetic domain revealing the magnetization process of the amorphous ribbons were characterized to explain the effect of P on magnetic properties and oxidation behavior. [ABSTRACT FROM AUTHOR]

Effects of Fe content on magnetic properties and bending ductility of FeSiBPC amorphous alloy ribbons before and after annealing were systematically investigated. It was found that all alloys had high amorphous forming ability and good soft magnetic properties after annealing. The transition temperature of bending ductility-brittleness decreases much faster than that of soft magnetic properties with the increase of Fe content. It is interesting that alloys with Fe content higher than 80 at.% exhibit good ductility before and after annealing at the optimal condition. The alloy with Fe content of 71 at.% is brittle even at as-spun state. The saturation flux density ( B s ) and coercivity ( H c ) decrease with decrease of the Fe content and deviate from a linear fitting tendency. The temperature asynchronism between magnetic properties and bending ductility of amorphous alloy ribbons was discussed. This work will bring a new perspective to study the annealing induced brittleness and a guidance for the future development of the amorphous alloys. [ABSTRACT FROM AUTHOR]

A leak element has been developed based on anodic aluminum oxide (AAO) by means of the shadow coating technique. The gas flow through the leak element can exhibit the molecular flow in the pressure range from high vacuum to atmospheric pressure for helium and other heavy gases, since the AAO is made of multi tubes with the diameter of about 70 nm. The shadow coating technique could achieve a specific number of tubes on AAO to satisfy the conductance required for vacuum applications. Some key characteristics of molecular flow are demonstrated according to the conductance measurement using difference method. The flow rate of any other test gases introduced in to the vacuum chamber can be predictable with the known flow rate of helium through the fabricated leaks. [ABSTRACT FROM AUTHOR]

In the present investigation, the glass forming ability (GFA), thermal stability, and soft magnetic properties of Fe 85 Si 6- x B 8 Cu 1 C x alloys are investigated by the substitution of C for Si. It was found that the GFA of C-containing alloys is remarkably enhanced when a certain amount of Si is replaced by C in a C-free alloy. The temperature interval between the first and second crystallization temperatures is also improved by C addition and reaches a maximum value of 169 °C for the as-spun Fe 85 Si 2 B 8 Cu 1 C 4 amorphous alloy. The Fe 85 Si 4 B 8 Cu 1 C 2 nanocrystalline alloy exhibits the best soft magnetic properties with the highest saturation magnetic flux density (B s) of 1.95 T and the lowest coercivity (H c) of 4.1 A/m, which corresponds to the highest grain number density (N d). The high GFA, large annealing window, low cost, and excellent soft magnetic properties enable the Fe 85 Si 2 B 8 Cu 1 C 4 nanocrystalline alloy as a material with wide applicability. Moreover, this work is highly beneficial in balancing the relationship between a high B s and sufficient GFA in the production of Fe-rich nanocrystalline alloys. • Adding C to Fe-Si-B-C-Cu alloys can improve both the GFA and thermal stability of the as-spun amorphous alloy ribbons. • Addition of appropriate amount of C to Fe-Si-B-C-Cu amorphous alloys can enhance their soft magnetic properties. • As-annealed Fe 85 Si 4 B 8 Cu 1 C 2 alloy exhibits a high B s of 1.95 T and low H c of 4.1 A/m. [ABSTRACT FROM AUTHOR]

In this paper, we systematically investigate the morphological characteristics and evolution process of plasma induced pitting damage (PIPD) during the inductively coupled plasma (ICP) etching of fused silica with subsurface damage (SSD). Plasma induced pits are found to have uniform diameter as opposed to SSD induced pits. PIPD evolves differently in physical and reactive etching. In physical etching, the pit diameter increases linearly with etching time due to the etching of pit sidewall, while the depth remains constant. In CHF 3 plasma, depth also increases with etching time. This is due to the redistribution of F-based etchant caused by the pit sidewall, which enhances the local etching rate at the pit bottom. The fact that with increasing etching time the diameter increases linearly but remains uniform implies that all the pits are generated at the same time. More particularly, the fitted line suggests that PIPD forms at the beginning of plasma process. [ABSTRACT FROM AUTHOR]

In this work, we introduce an optimum ICP etching technique that successfully removes the subsurface damage (SSD) layer of fused silica without causing plasma induced surface damage (PISD) or lateral etching of SSD. As one of the commonest PISD initiators, metal contamination from reactor chamber is prevented by employing a simple isolation device. Based on this device, a unique low-density pitting damage is discovered and subsequently eliminated by optimizing the etching parameters. Meanwhile etching anisotropy also improves a lot, thus preventing the lateral etching of SSD. Using this proposed technique, SSD layer of fused silica is successfully removed with a surface roughness of 0.23 nm. [ABSTRACT FROM AUTHOR]