In this study the soft magnetic alloy Fe-3Si-0.75P (wt%) was obtained by mechanical alloying through powder metallurgy. The processing included the formulation of metallic powder, wet milling for 1 h, 3 h, 6h and 9 h, in an attritor mill using alcohol P.A. as a lubricant. Cold compaction was then performed in a floating die under 600 MPa pressure and, finally the ring-shaped test specimens were sintered at 1150 °C for 1h. The electrical, physical and magnetic properties were then analyzed using the following assays: Laser granulometry, density, metallography, hysteresis curve and AC permeability, resistivity and XRD. The results showed a strong influence of milling time on magnetic properties of the alloy. There was a decrease in grain size with the milling time, which is likely the cause of increased in magnetic properties.

Currently the sports footwear market is very competitive, in which it is sought to produce products that provide high performance, using technology in the production processes as well as in the materials used. One of the main materials used in the composition of soles and midsole of these products is EVA (Ethylene-Vinyl Acetate), which brings several benefits such as cost reduction, comfort, lightness and softness. The injection molding process is the most efficient for obtaining EVA soles, however, EVA undergoes large expansions that may vary according to its formulation and geometry of the desired model. The objective of this work is to analyze the non-uniform deformation of EVA, used in the injection molding processes, as well as one method used to correct such distortions that occur in the expansion of this material. For this, a bibliographic review was carried out to analyze the chemical composition of the EVA, whose composition will determine the characteristics of expansion and softness. The work also addresses the steps of the injection process by analyzing the temperatures and pressure employed and an analysis of how to predict and correct the distortion in EVA expansion. It is proposed to use a section of a 3D model, where it is determined where compensations should be applied and using 3D modeling software.To analyze the generation of smaller bubbles in less thick regions of an EVA sole, a scanning electron microscope (SEM) analysis was performed. In addition, the measurements of the analyzed model were compared with the virtual model through a 3D scan. Hardness tests on the Asker C scale and injection simulations were also performed to analyze the cooling time of the part after leaving the mold, volumetric contraction that occurs in the extraction of the mold part, and the thicknesses of the walls of the product. The results indicate that the comparison of the models was within the accepted tolerance, which allows a variation in the expansion of up to 1mm in the length of the evaluated points. From the analyzes made in the scanning electron microscope and in the hardness test, it was possible to verify that in regions of smaller thickness and smaller volume, the EVA blend cannot have its total expansion, i.e., micro bubbles of gases generated in the expansion are smaller in these regions when compared to regions of greater volume and thickness. Consequently, these regions become denser and less soft. Simulations indicated that in regions where bubbles do not expand, there is also an early cooling of the material when compared to regions with higher volume, proving that the cooling time is directly linked to the EVA expansion rate.

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The aim of this work was to evaluate mass loss in each stage of the recycling process for metal recovery from PCBs of controllers and temperature indicators of cold chambers. The stages of process consists of grinding, particle size classification, magnetic and electrostatic separation. It was analyzed 13 kg of PCBs. These PCBs were crushed and ground. The ground material were subjected to magnetic and electrostatic separator. The losses in the comminution stages were 12.69 % and are lower than those found in other related works that used mixtures of different types of PCBs, whereas in this work only one model plates were analyzed. 27.2 % absolute mass loss we reached out after particle size separation with Tyler Series with 1 mm sieve presents the higher mass losses in the whole process and this fraction was not processed as it results in PCBs powder dust that interferes negatively in the electrostatic separation. Comparing the losses in the stages of shredding of PCBs employed in temperature controllers with other studies involving PCBs from the automotive industry and from computers and cell phones, is remarkable that this type of board presents significantly greater potential to be processed for recovery of its materials.

Resumo Este trabalho teve por objetivo o estudo de ligas sinterizadas a partir de Fe puro, FeP, FeSi e FeNi obtidas a partir do processo da Metalurgia do Pó e sua aplicação em núcleos de rotor e estator de servomotores, operando com corrente elétrica de armadura de alta freqüência, reduzindo assim, nestas frequências, as correntes parasitas, as quais causam perda de potência nestas máquinas. O estudo compreendeu obtenção de curvas de histerese destas diversas ligas, ensaios para avaliação de perdas elétricas e simulação em software de elementos finitos para obtenção de fluxo de entreferro e conjugado eletromagnético (torque). Os estudos teóricos e simulações foram realizados em um servomotor de topologia convencional e os testes foram realizados comparativamente a servomotores com núcleos obtidos a partir de chapas de aço laminadas. Nas simulações realizadas estaticamente, o torque instantâneo e o fluxo magnético no núcleo de Fe1%P resultaram valores próximos em relação às tradicionais chapas de aço laminadas. O núcleo de Fe1%P apresentou torque instantâneo de 1,59 N.m e fluxo magnético de 1,70 T e o núcleo de chapas de aço laminadas, respectivamente, 1,65 N.m e 1,66 T.Palavras-chave: Metalurgia do Pó. Servomotores. Simulação por elementos finitos. ABSTRACT This work aimed to study sintered alloys from pure Fe, FeP, FeSi and FeNi obtained by Powder Metallurgy process, and its application in rotor and stator cores of servomotors, operating with armature electric current in high frequency, thus reducing, in these frequencies, eddy currents, which cause loss of power in these machines. The study comprised obtaining hysteresis curves from these different alloys, tests to evaluate electrical losses and simulation in finite element software to obtain airflow and electromagnetic conjugate (torque). Theoretical studies and simulations were performed on a conventional topology of servomotor, and the tests were carried out comparatively to servomotors with cores obtained from rolled steel sheets. In the simulations performed statically, the instantaneous torque and the magnetic flux in the Fe1%P core resulted close values in relation to the traditional laminated steel sheets. The Fe1%P core had an instantaneous torque of 1.59 N.m and a magnetic flux of 1.70 T and the core of rolled steel sheets, respectively, 1.65 N.m and 1.66 T.Keywords: Powder Metallurgy. Servomotors. Finite Element Simulation.