Desarrollo de una planta piloto de materiales magnéticos

This paper presents the development achieved in the FONARSEC project execution, incorporated into the database of the Technological and Social Development Projects with which the assembly of a Magnetic Materials Pilot Plant of semi-industrial nature has been achieved for production of cores used in electrical and/or electronic industry. Unique assembly, due to its peculiarities, in Latin America and within the Mercosur scope, related to the energy sector. This plant produces amorphous and nanocrystalline magnetic materials that increase the effciency of some industrial equipment by up to 80%. This development has been achieved with the participation of two PyMEs that have contributed to generating this R&D platform in a Public and Private Associative Consortium that provides assistance to those interested in this technology.Fil: Pagnola, Marcelo Rubén. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Sirkin, Hugo Ricardo Mario. Instituto Nacional de Tecnología Industrial; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

From Fe3Si towards Fe3Ge in Finemet-like nanocrystalline alloys: Mössbauer spectroscopy

Nanocrystalline Finemet-type ribbons with different Si/Ge ratio [Fe73.5Si13.5-xGexNb 3B9Cu1 (x = 7, 8, 10 and 13.5)] were studied by means of Mössbauer spectroscopy and X-ray diffraction. The trend to form the non-stoichiometric DO3 Fe3Si structure in Finemet alloys (x = 0) is confirmed as Si is substituted for Ge. Results also indicate that the crystalline fraction increases when Si is gradually replaced with Ge. The hyperfine magnetic fields and the isomer shifts are characterised by a quasi-linear relationship with the Ge content of the nanocrystals.Fil: Moya, Javier Alberto. Universidad Católica de Salta; Argentina. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cremaschi, Victoria Juliana. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sirkin, Hugo Ricardo Mario. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

FINEMET type alloy without Si: Structural and magnetic properties

Magnetic and structural properties of a Finemet type alloy (Fe73.5Ge15.5Nb3B7Cu1) without Si and high Ge content were studied. Amorphous material was obtained by the melt spinning technique and was heat treated at different temperatures for 1 h under high vacuum to induce the nanocrystallization of the sample. The softest magnetic properties were obtained between 673 and 873 K. The role of Ge on the ferromagnetic paramagnetic transition of the as-quenched alloys and its influence on the crystallization process were studied using a calorimetric technique. Mössbauer spectroscopy was employed in the nanocrystallized alloy annealed at 823 K to obtain the composition of the nanocrystals and the amorphous phase fraction. Using this data and magnetic measurements of the as-quenched alloy, the magnetic contribution of nanocrystals to the alloy annealed at 823 K was estimated via a linear model.Fil: Muraca, Diego. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Cremaschi, Victoria Juliana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Moya, Javier Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Sirkin, Hugo Ricardo Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentin

First order reversal curve analysis on NdFeB nanocomposite ribbons subjected to Joule heating treatments

Amorphous precursors with composition Nd4.5Fe72−xCo3+xCr2Al1B17.5 (x = 0, 2, 7, 12) were thermally treated by the Joule heating technique with a linearly varying electrical current. The crystallization kinetics was followed by monitoring the resistance of the ribbons during the heating up to the final applied current. Crystallized nanostructured phases coexist with an amorphous matrix, as it was observed by means of Mössbauer Spectroscopy and X-ray diffraction. The irreversible magnetic response of the Joule heated ribbons was analyzed by the First Order Reversal Curves (FORC) diagram technique. For the optimal treatments, associated with the higher maximum energy products for each sample composition, it was found that the main interaction is of a strongly dipolar characteristic. Over annealed samples show a FORC diagram that gives into account of softening, due to grain growth, for those phases precipitated at the first crystallization stage. When it is measured at 20 K, the hardest magnetic sample (Fe = 72 at.%, Co = 3 at.%, Ifinal = 0.5 A), exhibits a diagram with characteristics corresponding to dipolar interactions of soft phases. This fact is consistent with an enhancement of the exchange length due to the increase in the soft phase stiffness as it is expected at low temperatures.Fil: Pampillo, Laura Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Saccone, Fabio Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Knobel, Marcelo. Universidade Estadual de Campinas; BrasilFil: Sirkin, Hugo Ricardo Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentin

Analysis of Fe78Si9B13 (%at.) ribbons of noncommercial scrap materials produced by melt spinning equipment

Purpose: The purpose of this paper is to present a ribbons production route of composition Fe78Si9B13 (%at.) using low cost noncommercial scrap materials to obtain usable magnetic cores by melt spinning technique and their characterization. This way, these may compete with the materials produced by conventional casting processes. Design/methodology/approach: The methodology is to design a master alloy with scrap different starting compositions, to which Fe is added to get the desired atomic ratio of components. With this starting alloy, using the method of melt spinning, in its variant of chill block melt spinning, are achieved amorphous ribbons with desired soft magnetic behavior. Then these ribbons are thermally treated for achieve nanocrystalline structures to improve the performance in the magnetic cores. Findings: The result of this paper shows that it is possible to recycle scrap materials, and re-used efficiently as components essential in part of electrical components. This way, these may compete with the materials produced by conventional casting processes. Research limitations/implications: The limitation of this work to ensure that the scrap materials used is reasonably adequate to accomplish obtaining the master alloy, i.e. having reduced impurities. Practical implications: The implications are important, because it assures that the components are recyclable and also high-tech in reference to energy saving that involves the production of amorphous and nanocrystalline materials in the electric industry. These products may compete with those produced by conventional casting processes. Social implications: The social implications lead to awareness in recycling and energy saving as an option for social progress in technology. Originality/value: The originality of the study is that it takes as a starting point for the final product (ribbon) noncommercial scrap materials of known composition and the obtained results are comparable to those that also are manufactured from the pure elements. The control of impurities is necessary in the production route. This way, these may compete with the materials produced by conventional casting processes. This process achieved a production with lower cost, high efficient energy products and high added value.Fil: Pagnola, Marcelo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería; Argentina. Universidad de Buenos Aires. Facultad de Ingenieria. Departamento de Fisica. Laboratorio de Sólidos Amorfos; ArgentinaFil: Malmoria, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería; Argentina. Universidad de Buenos Aires. Facultad de Ingenieria. Departamento de Fisica. Laboratorio de Sólidos Amorfos; ArgentinaFil: Barone, Marcelo Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería; Argentina. Universidad de Buenos Aires. Facultad de Ingenieria. Departamento de Fisica. Laboratorio de Sólidos Amorfos; ArgentinaFil: Sirkin, Hugo Ricardo Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería; Argentina. Universidad de Buenos Aires. Facultad de Ingenieria. Departamento de Fisica. Laboratorio de Sólidos Amorfos; Argentin

Influence of z/w relation in Chill Block Melt Spinning (CBMS) process and analysis of thickness in ribbons

Purpose: The purpose of this paper is to present an analysis over own and other authors data related to the process of Chill Block Melt Spinning (CBMS) and propose a model of analysis for interpreting. Design/methodology/approach: The methodology used in this work is to present the data analyzed by other authors, organize own data similarly to establish comparison, and established models and propose a possible physical processes interpretation. Findings: Similarity between own experimental data. with others data reported by other authors, both z/w ratio and the thicknesses of the films produced has been found. This allows us to establish an exponential decay of the parameters studied and possibly link it the Newtonian cooling to which the samples are subjected in its production. Research limitations/implications: This work is the first model set up to predict dimensions in design process by CBMS as a function of parameters of the ribbon production process. Practical implications: The prediction of the product dimensions, with adjusting the initial parameters, allows to improve the process of ribbon production, this saves tuning time of the machine and provides certainty in the molten material ejection. Social implications: The efficient production of magnetic materials lets save efforts in the raw material process preparing in magnetic cores for the energy sector. This, improves production besides benefit society by the final product and the energy savings. Originality/value: The value of this paper is to propose a model of analysis that allows standardize production parameters, and could even allow the use of these models in computer programs, process simulators in a more effective manner.Fil: Pagnola, Marcelo Ruben. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Barone, Marcelo Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Malmoria, Mariano Esteban Noe. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Sirkin, Hugo Ricardo Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentin

Structural and magnetic properties of Fe76P5(Si0.3B0.5C0.2)19 amorphous alloy

Recently, bulk amorphous alloys were produced in the Fe–B–Si–P–C system with high glass forming ability, excellent magnetic properties and the advantage of containing no expensive glass-forming elements, such as Ga, Y, Cr or Nb, having, therefore, a good perspective of commercial applications. In the present work, the Fe76P5(Si0.3B0.5C0.2)19 amorphous alloy prepared by two quenching techniques has been studied. Amorphous ribbons of about 40 μm thick were obtained by planar-flow casting together with cylinders having 1 and 2 mm diameter produced by copper mold injection casting. All the samples appear fully amorphous after X-ray diffraction analysis. A comprehensive set of thermal data (glass, crystallization, melting and liquidus temperatures) were obtained as well as a description of the melting and solidification processes. Mechanical microhardness tests showed that the samples have a hardness of 9.7 ± 0.3 GPa. Good soft-magnetic properties were obtained, including a high magnetization of 1.44 T and a low coercivity (4.5 A/m for ribbons and 7.5 A/m in the case of 1 mm rod samples, both in as-cast state). Thermomagnetic studies showed a Curie temperature around 665 K and the precipitation of new magnetic phases upon temperatures of 1000 K. Furthermore, the frequency dependence of magnetic losses at a fixed peak induction was studied. The results suggest the occurrence of a fine magnetic domain structure in bulk samples. The good soft magnetic properties of the bulk metallic glass obtained by copper mold casting for this particular Fe-based composition suggests possible applications in transformer cores, inductive sensors and other devices.Fil: Lavorato, Gabriel Carlos. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina. Universita di Torino; ItaliaFil: Fiore, G.. Universita di Torino; ItaliaFil: Tiberto, P.. Istituto Nazionale di Ricerca Metrologica. Electromagnetism Division; ItaliaFil: Baricco, M.. Universita di Torino; ItaliaFil: Sirkin, Hugo Ricardo Mario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; ArgentinaFil: Moya, J.A. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long". Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Tecnologías y Ciencias de la Ingeniería "Hilario Fernández Long"; Argentina. Universidad Católica de Salta; Argentin