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Enhancing the formability of FeSi6.5 steel by the anodic polarization

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International Journal of Minerals,Metallurgy and Materials 2022年第11期29卷 2072-2078页

作者： Dong Zhao Feng Ye Binbin Liu Haoyang Du Yaakov B.Unigovski Emmanuel M.Gutman Roni Shneck State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China State Grid Jilin Electric Power Research Institute Jilin 130021China department of Materials engineering Ben-Gurion University of the NegevBeer-Sheva 84105Israel

The effect of anodic polarization on the plastic deformation behavior and formability of FeSi6.5 steel at room temperature was experimentally investigated through uniaxial tensile and drawing of wire specimen in sulfuric acid solution with current densities of 0-40 mA/*** formability of the FeSi6.5 steel was significantly improved after the anodic *** plastic elongation of the specimen as an anode in the electrochemical environment was 4.4%-7%,but 2.7%in the *** drawing force under the anodic polarization decreased by 12.5%-26%compared to that in deionized *** softening is mainly attributed to the relief in work hardening caused by surface atomic *** work hardening mechanism of the FeSi6.5 steel wires under anodic polarization condition was analyzed using Hollomon equation and Voce relation combined with the Kocks-Mecking *** data support the view that the surface atom dissolution facilitates dislocation ***6.5 steel wires were obtained using electrochemical cold drawing and presented a smooth surface and good ductility without crack after five-pass drawing with a total cross-section area reduction of 88%.The drawing with the assistance of anodic polarization is a promising technology for processing hard and brittle metal materials.

关键词： FeSi6.5 steel plastic deformation anodic polarization Voce equation

Ordering and disordering of in situ grown MgAl-layered double hydroxide and its effect on the structural and corrosion resistance properties

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International Journal of Minerals,Metallurgy and Materials 2019年第12期26卷 1570-1577页

作者： Muhammad Ahsan Iqbal Michele Fedel department of industrial engineering University of Trento

A MgAl-layered double hydroxide(MgAl-LDH)protective film was developed on AA6082 substrates via the in situ hydrothermal growth method to obtain a distinct cauliflower-like LDH structure,and coated substrates were further heat-treated in air at temperatures from 100 to 250℃ to further improve the corrosion resistance of MgAl-LDH by taking advantage of the LDH memory effect;also,the effect of calcination on MgAl-LDH structural stability and the corresponding corrosion resistance properties were *** structural characterization of uncalcined and calcined LDH films were examined using scanning electron microscopy,energy-dispersive spectroscopy,X-ray diffraction,thermogravimetric analysis,differential scanning calorimetry,and Fourier transform infrared *** corresponding corrosion protection efficiency of the developed coating was studied through potentiodynamic polarization experiments and by electrochemical impedance *** with uncalcined MgAl-LDH,the calcined film showed a relatively lower corrosion current density and a higher impedance value,especially after heat treatment at 250℃.The findings demonstrate that calcination strongly affects the oriented growth of the LDH and causes an increase in the surface area and contraction of the basal spacing,which in turn caused a compact structure that substantially influenced the LDH corrosion resistance properties.

关键词： layered double hydroxide calcination in situ growth thin films corrosion protection

Thermal and Electrical Modelling of a CPV/T System Varying Its Configuration

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Journal of Thermal Science 2019年第1期28卷 123-132页

作者： RENNO Carlo department of industrial engineering University of Salerno

In this paper, the main aim is the performances modelling from the electrical and thermal point of view of a concentrating photovoltaic and thermal(CPV/T) system in order to evaluate the primary energy and economic savings respect to a traditional system, when the same energy loads are satisfied. This study is realized by both varying the CPV/T system configuration and considering two different users. In particular, the point-focus(PF), and linear focus(LF) configurations of the CPV/T system are considered in order to match the residential user and hotel energy loads. The CPV/T system is sized adopting as input data: the Direct Normal Irradiance(DNI) modelled by an artificial neural network and the users' energy demands. In these hypotheses, the performances of the PF and LF systems are evaluated and then compared for the two users located in Southern Italy, in terms of electrical and thermal energy production, cells number, space occupied, energy and economic savings and CO2 emissions avoided. Finally, the PF system shows a lower simple pay-back and a higher primary energy saving, while the space occupied by a LF system results to be lower respect to the PF configuration.

关键词： CPV/T system point-focus configuration linear focus configuration thermal analysis electrical analysis primary energy saving economic analysis

Ultrasound effects on zinc recovery from EAF dust by sulfuric acid leaching

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International Journal of Minerals,Metallurgy and Materials 2015年第4期22卷 353-362页

作者： K.Brunelli M.Dabalà department of industrial engineering University of Padua

In this work, an ultrasound-assisted leaching process was studied for the recovery of zinc from electric arc furnace （EAF） dust, in which zinc was mainly present in the form of franklinite （60%）. HydrometaUurgy is emerging as a preferred process for the recovery of a va- riety of metals, and the use of ultrasound could offer advantages over the conventional leaching process, especially for the dissolution of franklinite. Franklinite is a refractory phase that is difficult to leach and represents the main obstacle in conventional hydrometallurgy proc- essing. Atmospheric leaching with different sulfuric acid concentrations （0.2-2.0 M） at two temperatures （323 and 353 K） was performed. The tests were conducted using both conventional and ultrasound-assisted leaching. After the leaching tests, the solid residues were charac- terized by scanning electron microscopy （SEM） and X-ray diffraction （XRD） techniques, whereas the leach liquor was analyzed by induc- tively coupled plasma spectroscopy OCP）. The use of ultrasound facilitated the dissolution of franklinite at low acid concentrations and re- suited in a greater zinc recovery under all of the investigated operating conditions.

关键词： zinc recovery ultrasound electric arc furnaces dust leaching

The Drying of Pyridine Hydrobromide

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Chinese Journal of Chemical engineering 1998年第2期6卷 76-80页

作者： RenéD.Peralta Rodríguez Raúl G.López Campos Jaime Wisniak Jacinto G.Rodríguez Gómez Silvia Torres Rincón M.Esther Treviño Martínez Centro de Investigacion en Quimica Aplicada Blvd.Ing.Enrique Reyna Hermosillo No.140C.P.25100SaltilloCoahuilaMexico department of Chemical engineering Ben-Gurion University of the NegevBeer-ShevaIsrael

1 INTRODUCTIONThe drying of fine chemicals and pharmaceuticals is dominated by a number of special factorscompared to the drying of bulk *** include:very high value of product;lowthroughputs(typically,100 kg·h-1);materials that frequently possess toxic properties andare often sticky,pasty and difficult to handle when wet;the moisture to be evaporated ofteninvolves solvents;and multipurpose processing plants.

关键词： drying pyridine hydrobromide

Visible light driven mineralization of spiramycin over photostructured N-doped TiO2 on up conversion phosphors

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Journal of Environmental Sciences 2017年第4期29卷 268-276页

作者： Olga Sacco Vincenzo Vaiano Diana Sannino Paolo Ciambelli university of Salerno Department of Industrial Engineering

A novel visible light-active photocatalyst formulation（NdT/OP） was obtained by supporting N-doped TiO2（NdT） particles on up-conversion luminescent organic phosphors（OP）. The photocatalytic activity of such catalysts was evaluated for the mineralization process of spiramycin in aqueous solution. The effect of NdT loading in the range 15–60 wt.% on bulk and surface characteristics of NdT/OP catalysts was investigated by several chemicophysical characterization techniques. The photocatalytic performance of NdT/OP catalysts in the removal of spyramicin from aqueous solution was assessed through photocatalytic tests under visible light irradiation. Total organic carbon（TOC） of aqueous solution,and CO and CO2 gas concentrations evolved during the photodegradation were analyzed. A dramatic enhancement of photocatalytic activity of the photostructured visible active NdT/OP catalysts,compared to NdT catalyst,was observed. Only CO2 was detected in gas-phase during visible light irradiation,proving that the photocatalytic process is effective in the mineralization of spiramycin,reaching very high values of TOC removal. The photocatalyst NdT/OP at 30 wt.% of NdT loading showed the highest photocatalytic activity（58%of TOC removed after 180 min irradiation against only 31% removal after 300 min of irradiation of NdT）. We attribute this enhanced activity to the high effectiveness in the utilization of visible light through improved light harvesting and exploiting. OP particles act as ＂photoactive support＂,able to be excited by the external visible light irradiation,and reissue luminescence of wavelength suitable to promote NdT photomineralization activity.

关键词： Photocatalysis Visible light N-doped TiO2 Up-conversion phosphors Spiramycin mineralization

A Gradient Search Algorithm for the Maximal Visible Area Polygon Problem

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American Journal of Operations Research 2015年第3期5卷 168-178页

作者： Helman I. Stern Moshe Zofi department of industrial engineering and Management Ben-Gurion University of the Negev Beersheva Israel department of industrial Management Sapir College Sderot Israel

This paper provides a gradient search algorithm for finding the maximal visible area polygon (VAP) viewed by an interior point in a simple polygon P. The algorithm is based on a natural partition of P into convex sets, such that each element of the partition is associated with a unique analytical form of the area function. We call this partition a back diagonal partition of P. Our maximal VAP algorithm converges in a finite number of steps, and is polynomial with a complexity of , for a simple polygon P with n vertices, and r reflex vertices. We use the maximal VAP algorithm as a basis for a greedy heuristic for the well known guardhouse problem with a computation complexity of .

关键词： Maximal Visible Polygon Gradient Search Continuous Optimization Guardhouse Problem

End-life Prediction of Commercial PLA Used for Food Packaging through Short Term TGA Experiments: Real Chance or Low Reliability?

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Chinese Journal of Polymer Science 2014年第6期32卷 681-689页

作者： Ignazio Blanco department of industrial engineering University of Catania

A long-term （about nine months） isothermal degradation experiment of two different commercial polylactide （PLA） samples used for food packaging was carried out at a relatively low temperature （423 K）. Thermooxidative degradations of the same polymers were carried out in a thermogravimetric （TG） analyser, at higher temperatures （453 K 〈 T 〈 523 K）, under isothermal heating conditions. The obtained set of experimental TG data was used to determine the apparent activation energy （Ea） of degradation through two isothermal kinetic methods. The results from long-term experiment evidenced considerable mass loss for both PLA samples in the investigated period, but the experimental data were not in agreement with those from the short-term degradations at higher temperatures, thus suggesting a different degradation kinetics, and, then a low reliability of the lifetime predictions for polymers in service or degradation forecasts for the end of their life based on experiments at higher temperatures.

关键词： Lifetime prediction Degradation activation energy Kinetics of polymer degradation Thermogravimetry.

350°C - Thermal Stability of Austempered Ductile Iron

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材料热处理学报 2004年第5期25卷 195-200页

作者： M. Pellizzari M. Zadra A. Molinari department of Materials engineering and industrial Technologies University ofTrento ItalyDepartment of Materials Engineering and Industrial Technologies University ofTrento ItalyDepartment of Materials Engineering and Industrial Technologies University ofTrento Italy

The thermal stability of an ADI has been studied by isothermal aging at 350°C for 150 hours, measuring the amount of retained austenite and its carbon content by X-ray diffractometry. The influence of different austempering treatments, carried out at temperatures between 300 and 450°C (300, 330, 360, 410 and 450°C) and holding times between 15 and 60 minutes (15, 30, 45, 60), was considered. Thermal stability depends on whether austempering temperature is higher or lower than the ageing one. Thermal stability increases by increasing austempering temperatures, from 300° to 410°C. Samples treated at 410° and 450° show a lower austenite decomposition than samples at 300-330-360°C. A drop in stability is shown by increasing the austempering temperature from 410° to 450°C. The results have been interpreted on the basis of the austenite stability out of the processing window, which in turn depends on the austempering parameters.

关键词：热稳定性 ADI 等温淬火奥氏体延性铁