SIDerurgia-METalurgia-MATeriales: Publicaciones

2017

Revista: Mineral Processing and Extractive Metallurgy Review, 38 (2017) No. 4, 238-249.

Iron Ore Sintering: Environment, Automatic and Control Techniques.

D. Fernández-González, I. Ruiz-Bustinza, J. Mochón, C. González-Gasca y Luis Felipe Verdeja
 

Resumen:

Sintering is a process of agglomeration of iron ore fines, fluxes, recycled products, slag-forming elements, and coke with the purpose of achieving an agglomerated product with the suitable composition, quality and granulometry to be used as burdenmaterial in the blast furnace. However, the sintering process accounts for an important percentage of the ironmaking and steelmaking emissions, so the minimization of them will promote environmental and health improvements as well as economical profitability. Automatic and control systems contribute to all these objectives.

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Revista: Mineral Processing and Extractive Metallurgy Review, 38 (2017) No. 4, 254-264.

Iron Ore Sintering: Quality Indices.

D. Fernández-González, I. Ruiz-Bustinza, J. Mochón, C. González-Gasca y Luis Felipe Verdeja
 

Resumen:

Sinter plants process a mixture of iron ore fines, recycled ironmaking products, slag-forming agents and solid fuel (coke) with the finality of obtaining a product with the suitable characteristics (thermal, mechanical, physical, and chemical) for being fed to the blast furnace. With this objective a series of parameters are defined, including the nature and composition of each component of the mixture, and the conditions of the sintering process. Sinter characterization includes chemical and granulometric analysis, determination of the mineral phases in its structure, apart from a series of quality indices that includes reducibility, low temperature degradation, reduction degradation and Tumbler. Operated sinter plants with the maximum productivity are also important with the purpose of obtaining a sinter with uniform composition and quality for facilitating the steady state operation of the blast furnace.

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Revista: Mineral Processing and Extractive Metallurgy Review, 38 (2017) No. 4, 215-227.

Iron Ore Sintering: Process.

D. Fernández-González, I. Ruiz-Bustinza, J. Mochón, C. González-Gasca y Luis Felipe Verdeja
 

Resumen:

Sintering is a thermal agglomeration process that is applied to a mixture of iron ore fines, recycled ironmaking products, fluxes, slag-forming agents, and solid fuel (coke). The purpose of the sintering process is manufacturing a product with the suitable characteristics (thermal, mechanical, physical and chemical) to be fed to the blast furnace. The process has been widely studied and researched in the iron and steelmaking industry to know the best parameters that allow one to obtain the best sinter quality. The present article reviews the sintering process that the mixture follows, once granulated, when it is loaded onto the sinter strand. There, the sinter mixture is partially melted at a temperature between 1300-1480°C and undergoes a series of reactions that forms the sinter cake to be loaded into the blast furnace to produce pig iron.

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Revista: Kovove Mater, 55 (2017), 89-96.

Microstructures of a pressure die cast Al-8.5% Si-3.5% Cu alloy.

M. A. Barbés, M. J. Quintana, Luis Felipe Verdeja y R. González
 

Resumen:

Quantitative microstructural measurements of constituents of an Al-Si-Cu alloy, used to manufacture a part with thin sections by Pressure Die Casting (PDC), do not correspond to phase diagram calculations. A simulation of the liquid velocity when filling the mold was made in order to understand the relation between this parameter and pressure, cooling rate and the eutectic amount and morphology. Also, the microstructures of the same alloy solidified in a ceramic crucible (low cooling rate) and in a metal flask (high cooling rate) were compared to those obtained by PDC to analyze the role of pressure on the displacement of eutectic composition and formation of different eutectic morphologies. The amount of constituents varies with distance from the mold walls, producing higher or lower pressure zones, which may be estimated from the Al-Si phase diagram simulation at different pressures. As these pressures must be very high (~ 2 GPa), a possible explanation for the displacement of the eutectic point is the combination of high cooling rate of the manufacturing process, entrapment of gases during solidification and influence of the alloying elements.

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Revista: Protection of Metals and Physical Chemistry of Surfaces, 53 (2017) No. 2, 373-378.

Tribo-Corrosion Protection of Valves and Rotors using Cermet Layers Applied with HVOF.

M. J. Quintana, R. González, Daniel Fernández y Luis Felipe Verdeja
 

Resumen:

Protection of conventional steel parts in equipment that must withstand wear of the tribo-corrosion type (combination of heat and an aqueous medium) can be achieved by High Velocity Oxy-Fuel (HVOF) techniques, applying carbide-based cermet layers which decrease tribological and corrosion mechanisms. Three different carbide layers were applied to a ferritic-pearlitic steel in order to characterize properties such as sliding friction coefficient, phase identification, adhesion to the substrate, porosity, layer thickness and wear mechanisms. An example of a real rotatory equipment after a working campaign, both with and without protective layer is presented. The capacity of the protective layer to extend the life of parts like the one analyzed is evident even if zones of the layer are detached during the campaign.

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Revista: Mineral Processing and Extractive Metallurgy Review, 38 (2017) No. 1, 36-46.

Iron Ore Sintering: Raw Materials and Granulation.

D. Fernández-González, I. Ruiz-Bustinza, J. Mochón, C. González-Gasca y Luis Felipe Verdeja
 

Resumen:

Sintering is an agglomeration process that fuses iron ore fines, fluxes, recycled products, slag-forming elements and coke. The purpose of sintering is to obtain a product with suitable composition, quality and granulometry to be used as burden material in the blast furnace. This process is widely studied and researched in the iron and steelmaking industry. In this context, achieving an adequate sintered product depends on the adequate raw materials supply and the previous stage to the sintering process, granulation. For that reason, in this paper, the granulation process is studied as a consequence of being the source of pre-agglomerated materials for the subsequent sintering process. Thus, the main tests used to the determination of the properties are reviewed as well as the main granulation processes.

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2016

Revista: JOM, 68 (2016) No. 8, 2089-2095. DOI: 10.1007/s11837-016-2002-2 (link.springer.com/article/10.1007/s11837-016-2002-2?view=classic)

Optimization of sinter plant operating conditions using advanced multivariate statistics: Intelligent data processing.

Daniel Fernández-González, Ramón Martín-Duarte, Íñigo Ruiz-Bustinza, Javier Mochón, Carmén González-Gasca  y Luis Felipe Verdeja
 

Resumen:

Blast furnace operators expect to get sinter with homogenous and regular properties (chemical and mechanical), necessary to ensure regular blast furnace operation. Blends for sintering also include several iron by-products and other wastes that are obtained in different processes inside the steelworks. Due to their source, the availability of such materials is not always consistent, but their total production should be consumed in the sintering process, to both save money and recycle wates. The main scope of this paper is to obtain the least expensive iron ore blend for the sintering process, which will provide suitable chemical and mechanical features for the homogenous and regular operation of the blast furnace. The systematic use of statistical tools was employed to analyze historical data, including linear and partial correlations applied to the data and fuzzy clustering based on the Sugeno Fuzzy Inference System to establish relationships among the available variables.

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Revista: Metals, 6 (2016) No. 203.

Cold agglomeration of Ultrafine Oxidized Dust (UOD) from ferromanganese and silicomanganese industrial process.

María Ordiales, Juan Iglesias, Daniel Fernández-González, José Sancho-Gorostiaga, Alberto Fuentes y Luis Felipe Verdeja
 

Resumen:

Different wastes are generated in ferromanganese and silicomanganese alloy production. One of them is the ultrafine oxidized dust (UOD) produced in the collection and control of flying dusts in the ferroalloy industry. This waste has fairly high manganese content (20%-40% Mn), making it suitable to be a secondary raw material for the ferromanganese industry. This research proposes a method for the transformation of UOD into a useable raw material. Cold agglomeration is the best option, due to its low energy consumption. Portland cement and refractory cement are compared as suitable candidates in the management of the UOD for their reuse in the electric arc furnace feed.

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Revista: DYNA, 83 (2016) No. 195, 77-83.

Influence of strain rate and heat treatments on tensile and creep properties of Zn-0.15Cu-0.07Ti alloys.

María José Quintana, José Ovidio García, Roberto González y José Ignacio Verdeja
 

Resumen:

The use of Cu and Ti in Zn alloys improves mechanical properties as solid solution and dispersoid particles (grain refiners) may harden the material and reduce creep deformation. This is one of the main design problems for parts made with Zn alloys, even at room temperature. In this work the mechanical behavior of a Zn-Cu-Ti low alloy is presented using tensile tests at different strain rates, as well as creep tests at different loads to obtain the value of the strain rate coefficient m in samples parallel and perpendicular to the rolling direction of the Zn strip. The microstructure of the alloy in its raw state, as well as heat treated at 250°C, is also analyzed, as the banded structure produced by rolling influences the strengthening mechanisms that can be achieved through the treatment parameters.

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2015

Revista: Ironmaking & Steelmaking, 42 (2015) No. 8, 618-625.

Blast Furnace and Metallurgical Coke's Reactivity and its Determination by Thermal Gravimetric Analysis.

Juan Iglesias Rodero, José Sancho Gorostiaga, María Ordiales, Daniel Fernández, Javier Mochón, Íñigo Ruiz Bustinza, Alberto Fuentes y Luis Felipe Verdeja
 

Resumen:

The aim of the present work is to adapt tests that are typically used for blast furnace cokes such as coke reactivity index (CRI) and coke strength after reaction, to ferroalloy production in electric furnaces by developing easier equipment that meets with ISO 18894 standards. Moreover, a new technique has also been developed using thermal gravimetric analysis in order to quickly, inexpensively and reliably find the CRI parameter. As result of this work, a polynomial relationship between coke's reactivity and mass loss slopes of the record line obtained in the gravimetric thermal analysis tests was found.

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Revista: JOM, 67 (2015) No. 9, 1975-1985.

Potassium Permanganate as an Alternative for Gold Mining Wastewater Treatment.

María Ordiales, Daniel Fernández, Luis Felipe Verdeja y José Sancho
 

Resumen:

The feasibility of using potassium permanganate as a reagent for cyanide oxidation in wastewater was experimentally studied. Both artificial and production wastewater from two different gold mines were tested. The experiments had three goals: determine the optimum reagent concentration and reaction time required to achieve total cyanide removal, obtain knowledge of the reaction kinetics, and improve the management of the amount of reagent. The results indicate that potassium permanganate is an effective and reliable oxidizing agent for the removal of cyanide from gold mining wastewater.

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Revista: DYNA, 82 (2015) No. 190, 227-236.

Iron Ore Sintering. Part 3: Automatic and Control Systems.

Alejandro Cores, Luis Felipe Verdeja, Serafín Ferreira, Íñigo Ruiz-Bustinza, Javier Mochón, José Ignacio Robla y Carmen González Gasca
 

Resumen:

The sintering process involves a large number of parameters, more than 500, each of which exerts a greater or lesser influence and needs to be controlled, within the possible limits, in order to optimise productivity, process stability, and standardise the composition and quality of the sinter produced. To comply with environmental legislation, a pollution control system must monitor the particle matter and gases generated and emitted into the atmosphere by the sinter plant. Automation and control systems are vital tools to assist plant operators in the monitoring of each stage of the sinter production process.

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2014

Revista: Steel Research International, 85 (2014) No. 10, 1469-1476.

Transformations in the Iron- Manganese-Oxygen- Carbon System Resulted from Treatment of Solar Energy with High Concentration.

Javier Mochón, Íñigo Ruiz-Bustinza, Alfonso Vázquez, Daniel Fernández, Julia María Ayala,
María Florentina Barbés, and Luis Felipe Verdeja

 

Resumen:

With the aim of achieving a “zero waste” generation in industry, particularly in that of iron and steel, we propose studying the option to compete in this type of process, making use of an energy that, in addition to being free of contaminants, is also inexhaustible as is the case of solar energy. Solar energy is currently polarized has its greatest use in the production of electricity, either via thermal solar or photovoltaic, and it is also used as a low temperature heat source for water heating applications in households, hospitals, or hotels. Solar energy, when properly focused, can offer great potential for application in basic operations as well as processes of a chemical or chemical–metallurgical nature used for the obtaining, manipulation, and finishing of metals. Moreover, much waste from the iron and steel industry, make up a by-product whose exploitation requires high energy consumption in order that, either attempts are made to recycle them directly, or they are attempted to be taken advantage by feeding them, together with the conventional load, in reduction ovens. High temperature concentrated thermal solar energy could permit, on one hand, the generation of a high quality product (free of impurities which are detrimental to the process) using clean energy, and, thusly, fulfill the goal of achieving a “zero waste” generation.

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Revista: JOM, 66 (2014) No. 6, 1099-1105.

Synthesis of Commercial Products from Copper Wire-Drawing Waste.

Julia Ayala and Begoña Fernández

Resumen:

Copper powder and copper sulfate pentahydrate were obtained from copper wire-drawing scale. The hydrometallurgical recycling process proposed in this article yields a high-purity copper powder and analytical grade copper sulfate pentahydrate. In the first stage of this process, the copper is dissolved in sulfuric acid media via dismutation of the scale. In the second stage, copper sulfate pentahydrate is precipitated using ethanol. Effects such as pH, reaction times, stirring speed, initial copper concentration, and ethanol/solution volume ratio were studied during the precipitation from solution reaction. The proposed method is technically straightforward and provides efficient recovery of Cu from wire-drawing scale.

Trabajo derivado de un Proyecto-Contrato de I+D+i, financiado por SIA-Copper bajo la Dirección de José Pedro Sancho Martínez

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Revista: DYNA, 81 (2014) No. 183, 168-177.

Iron Ore Sintering Part 2. Quality Indices and Productivity.

Javier Mochón, Alejandro Cores, Íñigo Ruiz-Bustinza, Luis Felipe Verdeja, José Ignacio Robla and Fernando García-Carcedo

Resumen:

Sinter plants have to process mineral mixes in order to obtain sinter of a suitable composition and quality to be loaded into blast furnace. For this purpose a series of parameters need to be taken into account, such as the nature and composition of each component of the mineral mix and the conditions of manufacturing process. Sinter is subjected to in-depth characterisation in terms of chemical and granulometric analisys, determination of the mineral phases in its structure and of quality indices such as reductibility, low temperature degradation, reduction degradation, reduction degradation, and tumbler strengh. It is also important to operate sinter plants with productivity and to ensure a uniform sinter composition and quality so as to facilitate the steady state operation of the blast furnace.

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Revista: Steel Research International, 85 (2014) No. 2, 261-272.

The Influence of Gangue and Additives on the Divalent Iron Content of Magnetite Pellets.

Serafín Ferreira, Alejandro Cores, Jose Ignacio Robla, Luis Felipe Verdeja, Íñigo Ruiz-Bustinza, Fernando García-Carcedo y Javier Mochón.

Resumen:

During the pyroconsolidation of magnetite pellets in an aerobic atmosphere, the mineral practically oxidizes in the beginning stages of the process. However, as the temperature increases, the hematite dissociates into magnetite. The temperature at which this phenomena occurs depends on the additives present and is significantly lower than that corresponding to pure magnetite. In this paper a series of magnetite pellets were formed, varying the alkalinity (CaO+MgO)/(SiO2+Al2O3) from 0.4 to 1.9, and the MgO/CaO ratio from 0.12 to 1.3. The pellets were pyroconsolidated at temperatures ranging from 1050 to 1350ºC. Pellet structure was determined and analyzed using electron microscopy. The influence of additives and gangue composition was studied at the hematite disassociation temperature.

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Publicaciones 2013:

 

Revista: DYNA, 80 (2013) No. 180, 152-171.

Iron Ore Sintering Part 1. Theory and Practice of the Sintering Process

Alejandro Corés, Luis Felipe Verdeja, Serafín Ferreira, Íñigo Ruiz-Bustinza, Javier Mochón

Resumen:

Sintering is a process by which a mixture of iron ores, fluexs and coke is agglomerated in a sinter plant to manufacture a sinter product of a suitable composition, quality and granulometry to be used as burden material in the blast furnace. This process is studied and researched in the steelmaking industry in general, and in sinter plants in particular, as well as in universities and metallurgical research centres throughout the world. As a result of this research, and the experience accumulated over many years, the sintering process is well understood. Nevertheless, despite this good knowledge of sintering, there are still a number of issues that need to be studied. The present work provides information on the iron ores that form part of the mineral mix which, once granulated, is loaded onto the sinter strand where it is partially melted at a temperature of between 1250-1350 °C and undergoes a series of reactions that give rise to the formation of sinter; a material of a suitable composition and strength to be loaded into the blast furnace to produce pig iron.

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Revista: DYNA, 80 (2013) No. 182, 131-137.

Cooling Efficiency in Furnace Design.

Roberto González, María José Quintana, Íñigo Ruiz-Bustinza, Fernando García-Carcedo, Miguel Ángel Barbés, María Florentina Barbés

Resumen:

During melting, reduction or thermal treatment of a steel charge, the input of energy (either chemical or electrical) is indispensable to guarantee the viability of the process. Under these circumstances, it will be reasonable to design the furnace lining in such a way that heat loss through the walls is minimized. Nevertheless, it can be proved that, for some situations, it is more efficient to withdraw as much heat as possible from the walls than trying to thermally isolate the system. The work presents recommendations for the design of walls and cooling systems in furnaces obtained by quantitative analysis of temperatures reached in specific locations of the furnace using the nodal wear model. The analysis indicates that the wear process of the lining may be controlled if all the elements that intervene in the process are known.

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Revista: Journal of Iron and Steel Research International, 20 (2013) No. 1, 62-70.

Structural Ultrafine Grained Steels Obtained by Advanced Controlled Rolling.

Roberto González, José Ovidio García, Miguel Ángel Barbés, María José Quintana, Luis Felipe Verdeja and José Ignacio Verdeja

Resumen:

Steels with ultrafine grains (lower than 5 μm), which usually known as ultrafine ferrite or ultrafine grained materials, are presently the object of intense research, because of the improvement in resistance and fracture toughness they may reach compared to conventional steels (with grain sizes above this value). It is shown that the forenamed steels designated in the Euronorm EN 10149-2, which are manufactured by advanced techniques of controlled rolling and mainly used in automotive industry, have an ultrafine grain size in the range of 2. 5 to 3. 5 μm, and with elastic yield stresses higher than 400 MPa. Based on the Morrison-Miller criterion, it is shown that values of the strain-hardening coefficient lower than 0. 08 would make the industrial application of these steels unfeasible.

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Revista: Steel Research International, 84 (2013) No. 2, 207-217.

Magnetite Production from Steel Wastes with Concentrated Solar Energy.

Íñigo Ruiz-Bustinza, Inmaculada Cañadas, José Rodríguez, Javier Mochón, Luis Felipe Verdeja, Fernando García-Carcedo and Alfonso Vázquez

Resumen:

In order to achieve a balanced development in the application of materials for structural or functional purposes, one of the priority objectives of future work is to achieve the goal of "zero waste" in the different production lines. As would be expected from what was agreed in the Kyoto Protocol and the meetings of Copenhagen 2009 and Cancun 2010, the production of clean energy will be strongly encouraged in the future, and indeed that is already the case now. Taking that into consideration, while the promotion of clean energy production is mainly directed toward electricity, solar thermal is quite interesting because of its direct application to metal mining and the chemical processes used in the sustainable development of materials. The combination of both objectives, "zero waste" and "clean energy", may pose an interesting challenge in the development of primary iron and steel, as well as in other areas of metal production and even in the field of mining. The help of solar thermal energy, which can be concentrated to reach high temperatures, is a tool that could support both the direct production and the recycling of waste steel, in particular waste which is physically and chemically the worst for the environment. This would mean that the environment itself, solar energy, is in fact the key to environmental protection.

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Revista: JOM, 65 (2013) No. 8, 1007-1014.

Reuse of Anode Slime Generated by the Zinc Industry to Obtain a Liquor for Manufacturing Electrolytic Manganese.

Julia Ayala and Begoña Fernández

Resumen:

A hydrometallurgical process is proposed in this article to recover manganese from a zinc electrowinning residue. The article describes the digestion-leaching experiments, precipitation and electrowinning assays to recover Mn from this residue. Anode slime is treated with sulfuric acidic in a furnace within a temperature range of 400-450ºC, leached with water, and the filtered. The results show that the dissolution of manganese increases with increasing temperature in the digestion step. The recovery yield of manganese was higher than 90%. As manganese electrolysis requires an electrolyte free of Zn, Ni, Co, and Cu pollutants, the sulfuric acid liquor needs a purification step. Na2S is used to remove pollutants. The results obtained in this study have shown that the proposed process for the recovery of manganese from this type of residue is technically viable.

Trabajo derivado dentro de un Proyecto-Contrato de I+D+i, financiado por Ferroatlántica bajo la Dirección de José Pedro Sancho Martínez.

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Revista: Journal of Failure Analysis and Prevention, 13 (2013) No. 3, 368-376.

Superplastic HSLA Steels: Microstructure and Failure.

Sara Fernández, María José Quintana, José Ovidio García, Luis Felipe Verdeja, Roberto González and José Ignacio Verdeja

Resumen:

Certain materials can show superplasticity when traction tested at temperatures higher than 50% of their melting point and with low strain rates (ε· < 10-2 s-1), showing very high elongations (>100%) without localized necking and mainly intergranular fractures. This behavior requires that the starting grain size is small (<10 μm) so the flow of matter can be non-homogeneous (sliding and rotating of the grain boundaries, accommodated by diffusion). This work presents the superplastic characteristic of shipbuilding steel deformed at 800 ºC and a strain rate slower than 10-3 s-1. The fine grain size (5 μm) is obtained when using Nb as a microalloying element and manufactured by controlled rolling processes (three stages). After the superplastic deformation, the steel presents mixed fractures: by decohesion of the hard (pearlite and carbides) and ductile (ferrite) phases and by intergranular sliding of ferrite/ferrite and ferrite/pearlite, just as it happens in stage III of the creep behavior. This is confirmed through the Ashby–Verrall model, according to which the dislocation creep (power-law creep) and diffusion creep (linear-viscous creep) occur simultaneously.

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Publicaciones 2012:

-Ferritic Grain Size: An Ignored Factor, in fact, in the Failure Analysis of the Sinking of a Famous Ship.

-Superplasticity of Ultrafine Grained Low-Alloy Steels.

Publicaciones 2010:

-Results of the Application of the Mdn in the Improvement of the Design of an Electrical Furnace that produces Low Carbon Ferromanganese.

-Ultrafine Grained HSLA Steels for Cold Forming.

-Machinability Improvement Through Heat Treatment in 8620 Low-Carbon Alloyed Steel.

-A New “User-friendly” Blast Furnace Advisory Control System Using a Neural Network Temperature Profile Classifier.

-Some kinetics aspects of chlorine-solids reactions.

Publicaciones 2009:

-Determinación de los coeficientes de capa límite mediante el Modelo de Desgaste Nodal (MDN) para el estudio de la corrosión del crisol de alto horno.

-Microtextural aspects of the chemical corrosion in Pierce-Smith converters (PSC).

-Bottom design optimisation of electric arc furnace for ferromanganese production using nodal wear model.

-Características sólido-fluido en el crisol del horno alto según el modelo de desgaste nodal (MDN).

-Above Burden Temperature Data Probes Interpretation to Prevent Malfunction of Blast Furnaces- Part 1: Intelligent Information Preprocessing.

-Above Burden Temperature Data Probes Interpretation to Prevent Malfunction of Blast Furnaces- Part 2: Factory Applications.

Publicaciones hasta 2008:

-Ultramarine blue from Asturian “hard” kaolins.

-Design of Blast Furnace Crucibles by Means of the Nodal Wear Model.

 

Congresos 2013

Congreso: Materials Science and Technology (MS&T) 2013
October 27-31, 2013, Montreal, Quebec, Canada
Advanced Steel Metallurgy: Design, Processing, and Technological Exploitation

 

Microstructural Changes of a Construction Steel Caused by Hot Deformation.

José Ignacio Verdeja, María José Quintana, Roberto González and Luis Felipe Verdeja

 

Resumen:

A construction steel (shipbuilding strip) obtained by Advanced Thermomechanical Controlled Rolling Processes presents a room temperature banded ferrite-pearlite microstructure, and when superplastically deformed at 800°C with a strain rate of 5.85x10-5 s-1, the bands disappear as there is grain boundary sliding and grain cluster rotation. Nevertheless, the superplastic deformation does not imply a decrease in mechanical properties, as room temperature tests with strain rates of 1.46x10-3 s-1 with the steel previously deformed in superplastic conditions (until a 110% of straining) result in similar mechanical data. If the steel is deformed at 750°C with low strain rates, cooling results in a microstructure formed only by ferrite and carbides (the pearlitic phase disappears). This behavior may be explained, from a thermodynamical point of view, by the effect of negative hydrostatic pressure during the tensile test and the pronounced ferrite- and carbide-former capacity of Ti and Nb microalloying elements.
The samples, tensile tested, in both the hot rolled raw state and superplastically deformed and then room temperature tested, show in the fracture surface SEM analysis almost identical features: decohesions surrounding MnS and (C,N)(Ti,Nb) precipitates and between ferrite and pearlite grains, as well as bedding.

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Congreso: Innovative Manufacturing Technology/ Innowacyjne Technologie Wytwarzania
2013, Instytut Zaawansonwanych Technologii Wytwarzania, Cracovia, Polonia
 

Tribo-Corrosion Protection of Valves and Rotors Using Cermet Layers Applied with HVOF.

Julio Sánchez, Miguel Ángel Barbés, Roberto González and Luis Felipe Verdeja

 

Resumen:

The economic viability of equipment in industrial facilities that perform organic processes depends on the capacity of auxiliary equipment, such as valves or rotors, to withstand wear of the tribo-corrosion type (combination of heat and an aqueous medium). The use of Surface Engineering Techniques such as High Velocity Oxy-Fuel (HVOF) in order to apply carbide based cermet layers and showing very positive results in decreasing tribological and corrosion mechanisms, is still industrially evaluated against the use of wear resistant bulk materials. A comparison, after a working campaign, between non-protected and HVOF treated parts is presented.

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Otros artículos de interés:

 


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