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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 458-465页

作者： Rocio Ochoa Alfredo Flores Jesus Torres cinvestav-saltillo

The aluminothermic reduction of zinc oxide（ZnO） from alkaline battery anodes using molten Al may be a good option for the elaboration of secondary 7000-series alloys. This process is affected by the initial content of Mg within molten Al, which decreases the surface tension of the molten metal and conversely increases the wettability of ZnO particles. The effect of initial Mg concentration on the aluminothermic reduction rate of ZnO was analyzed at the following values： 0.90wt%, 1.20wt%, 4.00t%, 4.25wt%, and 4.40wt%. The ZnO particles were incorporated by mechanical agitation using a graphite paddle inside a bath of molten Al maintained at a constant temperature of 1123 K and at a constant agitation speed of 250 r/min, the treatment time was 240 min and the ZnO particle size was 450？500 mesh. The results show an increase in Zn concentration in the prepared alloys up to 5.43wt% for the highest initial concentration of Mg. The reaction products obtained were characterized by scanning electron microscopy and X-ray diffraction, and the efficiency of the reaction was measured on the basis of the different concentrations of Mg studied.

关键词： aluminothermic reduction alkaline batteries zinc oxide waste utilization aluminum zinc magnesium alloys

EBSD Investigation on Effect of Cooling Rate on Microstructure and Transformation Textures of High Strength Hot-rolled Steel Plates

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Journal of Iron and Steel Research International 2016年第3期23卷 261-269页

作者： Nancy M.LOPEZ GRANADOS Armando SALINAS RODRIGUEZ Department of Metallurgical Engineering and Materials Science Center of Research and Advanced StudiesCINVESTAV-Unidad Saltillo

The effect of cooling rate on the microstructure and transformation textures of high strength hot-rolled steels was *** treated samples subjected to different cooling conditions were characterized by optical and scanning electron microscopes using orientation imaging microscopy（OIM）.The experimental results demonstrate that there is a significant effect of cooling rate on microstructures and textures resulting from phase *** cooling rates lead to the appearance of the cube（001）[010],rotated cube（001）[110]/（001）[110],Goss（110）[001]and rotated Goss（110）[110]*** contrast,textures developed at rapid cooling rates are preferably of Cu（112）[111],Br（110）[112],transformed Cu（113）[110]and transformed Br（332）[113]/（112）[131].These texture changes are attributed to the selective character of the phase *** OIM technique was used to have a better understanding of the formation of phases and their relationship between microstructure and processing *** volume fraction of micro-constituents resulting from phase transformation such as bainite,martensite and different types of ferrite,can be measured satisfactorily by this technique correlating image quality of EBSD patterns to specific phases.

关键词： orientation imaging microscopy texture phase transformation microstructure steel

Characterization by EBSD of Antimony-calcium Rich Phases Formed during Purification of Aluminum Scrap

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Journal of Wuhan University of Technology(Materials Science) 2013年第4期28卷 647-649页

作者： MUIZ Rodrigo FLORES Alfredo ORTIZ Juan RODRíGUEZ Nelly MARTíNEZ Fernando LUNA Jesús OROZCO Pilar Faculty of Engineering Autonomous University of Coahuila Camporedondo Unit cinvestav saltillo Unit Department of Metal Mechanics Technological Institute of Saltillo Faculty of Engineering Autonomous University of Zacatecas

We studied the influence of antimony on the modification rate of the silicon eutectic with sodium and/or strontium for castiig of A1-Si alloys, and introduced controlled Ca and Sb to the system and studied the resulting compounds, which were determined to be CazSb and A1Sb. Scanning electron microscopy together with the complementary technique of electron backscatter diffraction （EBSD） were used to characterize the materials. The experimental results provided the basis for us to establish that antimony removal from AI occurs mainly through the reaction （Sb）A1 ＋ 2Ca = Ca^Sb ＋ A1.

关键词： aluminum alloys antimony contamination modification

Microstructural Feature of As-cast A-356 Alloy Modifiers with the Addition of SrO

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Journal of Wuhan University of Technology(Materials Science) 2014年第3期29卷 617-619页

作者： MU?IZ Rodrigo FLORES Alfredo ORTIZ Juan RODRíGUEZ Nelly MARTíNEZ Fernando OROZCO Pilar LUNA Jesús Equihua Fabián García Adrián Faculty of Engineering Autonomous University of Coahuila Camporedondo UnitSaltillo Coahuila México cinvestav saltillo Unit Department of Metal Mechanics Technological Institute of Saltillo Faculty of Engineering Autonomous University of Zacatecas FIME Autonomous University of Coahuila Unit

To explore the effect of strontium on the structure of as-cast A356 alloy, the strontium was incorporated to the alloy by metallothermic reduction of SrO where the mineral was added to the melt through the submerged powders injection technique. The evaluation of the modification of the eutectie silicon and the chemical analysis of samples were done using optical microscopy （OP） and inductively coupled plasma （ICP）, respectively, while microstructural analyses by scanning electron microscopy （SEM）, and the injection time was variable. Magnesium was added to the melt to increase the reactivity and reduce the surface tension of the molten aluminum. It was possible to increase the strontium content from 0 to 0.027% after 20 minutes treatment. This concentration was sufficient to bring about full modification structure of eutectic silicon of as cast alloy A 356 and the acceptable quality metallurgical of alloy.

关键词： modification microstmcture strontium eutectic silicon submerged powder injection

Cerium extraction by metallothermic reduction using cerium oxide powder injection

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Journal of Rare Earths 2011年第1期29卷 74-76页

作者： J.S.Luna A A.Flores V R.Muiz V A.F.Fuentes J.Torres N.Rodríguez R J.C.Ortiz P.Orozco cinvestav Unidad saltillo Saltillo-Monterrey Highway Km.13.5P.O.Box 66325000SaltilloCoahuilaMéxico Faculty of Engineering Autonomous Univer-sity of CoahuilaCamporedondo UnitSaltilloCoahuilaMéxico Department of Metal Mechanics Technological Institute of SaltilloV.Carranza Blvd 2400SaltilloCoahuilaZC 25280México Academic Unit of Engineering Autonomous University of CoahuilaLopez Velarde Av.ZacatecasZac.ZC 98060

This work presented the feasibility of cerium recovery by Al-Mg alloy through the metallothermic reduction of CeO2 to obtain a master alloy Al-4%Ce. The master alloy obtained in this investigation was for the grain refinement and modification of Al-Si alloys. The reagent was incorporated into a molten alloy using the submerged powder injection technique, and metallic samples were obtained during injection. Chemical and microstructural analyses （by inductively coupled plasma （ICP） and scanning electron microscopy （SEM）, respectively） confirmed the possibility of Ce uptake in the bath （0 to 4 wt.%）, as CeO2 was reduced through metallothermic reactions in the molten alloys. Based on the characterization of reaction products, the sequence of the reaction was proposed.

关键词： cerium recovery metallothermic reduction reaction products rare earths

Thermodynamic and experimental studies on removal of calcium and sulfate ions from recycling water of complex sulfide flotation operations

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Transactions of Nonferrous Metals Society of China 2021年第10期31卷 3116-3127页

作者： Elvis BUSTOS-FLORES Martha Araceli ELIZONDO-ÁLVAREZ Alejandro URIBE-SALAS Department of Metallurgical Engineering CINVESTAV-IPNUnidad Saltillo25900Ramos ArizpeCoahuilaMexico

A chemical method for removing calcium sulfate saturated solutions(0.016 mol/L CaSO_(4))using barium chloride(BaCl_(2)∙2H_(2)O)and sodium phosphate(Na_(3)PO_(4))was experimentally *** main interest is to remove these ions from the solution through the precipitation of two solid species:sulfate(SO_(4)^(2−))as barite(BaSO4),and calcium(Ca^(2+))as hydroxyapatite(Ca_(5)(PO_(4))_(3)OH).Additionally,a solid/liquid separation method(i.e.,flotation)was explored,using oleic acid and dodecylamine as *** results show that,the chemical treatment of saturated solutions at 60℃,pH 11.5 and using 3.9 g/L BaCl_(2)·2H_(2)O and 1.6 g/L Na_(3)PO_(4),promotes the precipitation of barium sulfate and calcium-deficient hydroxyapatite(Ca_(10−x)(HPO_(4))_(x)(PO_(4))_(6−x)(OH)_(2−x)),with residual concentrations of calcium and sulfate below 0.10 and 5 mg/L,*** residual calcium concentration increases to 28 mg/L when using the same amount of reactants,at temperature and pH values below those *** highest flotation recovery of hydroxyapatite with oleic acid at pH 9.5 was about 80%,while that of barite floated with dodecylamine at pH 6.5 was about 90%.

关键词： calcium sulfate dodecylamine oleic acid barite hydroxyapatite flotation separation

Greenhouse Gas Emissions and Growth of Wheat Cultivated in Soil Amended with Digestate from Biogas Production

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Pedosphere 2017年第2期27卷 318-327页

作者： Liliana PAMPILLON-GONZALEZ Marco LUNA-GUIDO Victor Manuel RUIZ-VALDIVIEZO Olivia FRANCO-HERNANDEZ Fabign FERNANDEZ-LUQUENO Oetavio PAREDES-LOPEZ Gerardo HERNANDEZ Luc DENDOOVEN PhD Program on Science Technology and Society Cinvestav IPN 2508 Mexico DF 07360 (Mexico) Laboratory of Soil Ecology Laboratorio de Matemdticas Aplicadas y Cdmputo de Alto Rendimiento Cinvestav-Edomex (ABACUS) Cinvestav IPN 2508 Mexico DF 07360 (Mexico) Department of Chemistry Unidad Profesional Interdisciplinaria de Biotecnologla-Instituto Politdcnico Nacional (UPIBI-IPN) Me- xico DF 07340 (Mexico) Sustainability of Natural Resources and Energy Program Cinvestav-Saltillo 1062 Coahuila 25900 (Mexico) Department of Biotechnology and Biochemistry Cinvestav Irapuato 36821 (Mexico)

Digestate, the product obtained after anaerobic digestion of organic waste for biogas production, is rich in plant nutrients and might be used to fertilize crops. Wheat （Triticum spp. L.） was fertilized with digestate, urea, or left unfertilized and cultivated in the greenhouse for 120 d. Emissions of greenhouse gasses （carbon dioxide （CO2）, methane （CH4）, and nitrous oxide （N20）） were monitored and plant growth characteristics were determined at harvest. The digestate was characterized for heavy metals, pathogens, and C and N mineralization potential in an aerobic incubation experiment. No Salmonella spp., Shigella spp., or viable eggs of helminths were detected in the digested pig slurry, but the number of faecal coliforms was as high as 3.6 ~ 104 colony-forming units （CFU） g-1 dry digestate. The concentrations of heavy metals did not surpass the upper limits established by US Environmental Protection Agency （EPA）. After 28 d, 17% of the organic C （436 g kg-1 dry digestate） and 8% of the organic N （6.92 g kg-1 dry digestate） were mineralized. Emissions of CO2 and CH4 were not significantly affected by fertilization in the wheat-cultivated soil, but digestate significantly increased the cumulative N20 emission by 5 times compared to the urea-amended soil and 63 times compared to the uncultivated unfertilized soil. It could be concluded that digestate was nutrient rich and low in heavy metals and pathogens, and did not affect emissions of CH4 and CO2 when applied to a soil cultivated with wheat, but increased emission of N20. Key Words： biodigester, C and N mineralization potential, faecal coliform, heavy metal, pathogen, pig slurry

关键词： biodigester C and N mineralization potential faecal coliform heavy metal pathogen pig slurry

城市废玻璃作为水泥基材料在化学激发胶凝材料中的潜在应用（英文）

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硅酸盐学报 2015年第10期43卷 1441-1448页

作者： J Ivan ESCALANTE-GARCIA Center for Research and Advanced Studies Cinvestav Campus Saltillo Av. Industria Metalfirgica 1062 Parque Industrial Saltillo-Ramos Arizpe Ramos Arizpe Coahuila CP 25900 Mexico

世界城市地区的人口不断增加,按此趋势发展,到2025年世界城市人口将达到43亿。与此同时,城市生活垃圾也逐渐增加,到2025年,将从现在的13亿吨增加到22亿吨。在这些垃圾中,玻璃占5%,而且只有不到30%可循环利用,这意味着4 600万吨是填埋处... 详细信息

世界城市地区的人口不断增加,按此趋势发展,到2025年世界城市人口将达到43亿。与此同时,城市生活垃圾也逐渐增加,到2025年,将从现在的13亿吨增加到22亿吨。在这些垃圾中,玻璃占5%,而且只有不到30%可循环利用,这意味着4 600万吨是填埋处理的。到2025年大约7 700万吨废弃玻璃需要进行填埋处理。尽管玻璃可以回收利用,但由于各方面原因使得玻璃的回收利用非常复杂,其中之一是因为需对玻璃进行颜色分类处理。目前,废玻璃已经用于替代部分硅酸盐水泥和骨料,但存在碱骨料反应的风险。废玻璃作为化学激发胶凝材料具有很大的潜力。但是关于该方面的研究很少,主要问题是将废玻璃作为碱激发胶凝材料使用时,其部分水化产物易溶于水。使用碱性激发剂激活其他含钙胶凝材料,如碳酸盐、矿粉等复合胶凝材料是可行的,且可得到性能优异的净浆和混凝土。讨论不同废玻璃水化反应产物的组成和结构,分析将废玻璃作为胶凝材料再利用在玻璃循环利用方面的可行性和优势。

关键词：钠-钙-硅玻璃:废玻璃碱激发胶凝材料替代胶凝材料

A Numerical Study Comparing the Effect on Residual Stresses of Two Different Types of Projectiles During Shot Peening

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Computers, Materials & Continua 2016年第3期51卷 203-215页

作者： J.Solórzano-López F.A.García-Pastor Angélica Flores-Luna UNAM Facultad de QuímicaCiudad de MéxicoMéxico cinvestav Unidad saltillo CoahuilaMéxico TecNM Instituto Tecnológico de Tláhuac IIICiudad de MéxicoMéxico

Shot peening is a widely used technique to improve fatigue life in metallic *** processing technique introduces a subsurface compressive residual stress field through a plastic deformation of the surface caused by the impact of a large number of high-speed *** are a number of parameters that affect the residual stress field depth and *** effects of the impact angle,shot speed and shot geometry are currently being *** particular,substituting spherical cast shots by cylindrical cut wire shots is an attractive option,especially in terms of *** effect of shot geometry on residual stresses,however,needs to be further *** industrial-scale experimentation is costly and cumbersome,mathematical modeling offers a convenient alternative to carry out this type of *** present work shows a comparison between the residual stresses generated by the impact of spherical and cylindrical projectiles on a steel *** threedimensional model was developed using ABAQUS finite element commercial software(Release 6.12,Dassault Systémes,France).The results show that cylindrical shots generate residual stress fields t hat a re higher in magnitude than t hose generated by a spherical ***,the residual stress field of cylindrical shots impacting the surface at an oblique angle shows an important degree of *** effect is not found when spherical shots impact the surface at the same oblique angle.

关键词： Shot Peening Finite element method Residual Stresses

Nucleation of Fe-Rich Intermetallic Phases on α-Al_(2)O_(3) Oxide Films in Al-Si Alloys

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Journal of Minerals and Materials Characterization and Engineering 2015年第1期3卷 15-25页

作者： Pilar Orozco-Gonzalez Manuel Castro-Roman Simitrio Maldonado-Ruiz Sergio Haro-Rodriguez Fabian Equihua-Guillen Rodrigo Muniz-Valdez Salvador Luna-Alvarez Miguel Montoya-Davila Alejandra Hernandez-Rodriguez Academic Unit of Engineering Autonomous University of ZacatecasZacatecasMexico cinvestav saltillo SaltilloMexico Faculty of Engineering Autonomous University of CoahuilaMexico

Nucleation of Fe-rich intermetallic phases on α-Al2O3 oxide films was analyzed in five experimental Al-Fe-Mn-Si alloys. In an attempt to verify the role of α-Al2O3 films in nucleating Fe-rich intermetallics, experiments have been conducted under conditions where formed in situ oxide films were present. Some Fe-rich intermetallics are observed to be related with the oxide films in the microstructure, the present results are in accordance with some research that suggest that the Fe-rich intermetallic phases nucleate upon the oxide films. The intermetallic phases and α-Al2O3 films were unambiguously identified with the help of complementary techniques such as thermal analysis, SEM/EDS and X-ray diffraction.

关键词： Aluminum Alloys Intermetallics Nucleation Crystal Growth Oxide Films