FRANK FERRER SENE
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Artigo IPEN-doc 24722 Obtention of WCuNi composite material using powder metallurgy for gamma (γ) radiation attenuation2017 - CIONE, F.C.; SOUZA, A.C.; SENE, F.F.; GOMES, M.P.; SOARES, E.P.; ROSSI, J.L.This work aimed to obtain a composite material WCuNi using the powder metallurgy. This composite is usable as material for the attenuation of gamma radiation (γ). The tungsten (W) is the main shielding element in this composite. The tungsten has high density (19.25 g.cm-3), high melting point (3,422 °C) and is presented as matrix of the composite. In order to meet the need for sintering with temperatures below 1,200 °C, the liquid phase sintering technique was used. For preparation of the samples, shape and size of the particles of the metal powders were analyzed. With the intention of homogenize the distribution of the metallic powders and to reduce the average particle size, a ball mill was used for 24 hours. After grinding, the particle size analysis showed that the mean particle size in WCuNi composition was 12 μm. The powder mixture was compacted in isostatic press at 200 MPa pressure. The samples were sintered at 1,100 °C and at 2,100 mbar pressure of reducing atmosphere (H2) for 8 hours. The formation of the isomorphic system CuNi is responsible for giving the mechanical characteristic of solid to the composite WCuNi. Optical and electronic microscopy (SEM) with EDS were undertaken to characterize the samples. The classical scientific method of experimentations with gamma radiation of the cobalt-60 source by attenuation of the energies was employed to study the effects on the samples. For the energies of 1,173 MeV and 1,332MeV the experimental method indicated the necessity of 11.95 mm of thickness for the solid compound W8Cu1Ni with the obtained density of 11.46 g.cm-3 to attenuate the energy to level allowed for occupationally exposed persons. The experimental values obtained were compared with values calculated by XCOM software database (NIST) of 12.45 mm and convergence of values was observed.Artigo IPEN-doc 23886 Synthesis and characterization of Ni-Mo sintered alloy foils for microwave tube manufacturing2013 - SENE, FRANK F.; SANTOS, VINICIUS O.; MOTTA, CLAUDIO C.The Ni-Mo composite alloy, to be used in microwave vacuum tube manufacturing, was prepared from metal powders previously homogenized, pressed and sintered at 1200oC by induction heating. The Ni-Mo sintered discs were annealed at 1150oC for 20min, and submitted to the roller process in 5 cycles to obtain a thin foil with 0.10 mm of thickness, for brazing process adopted to join the cathode components. The samples were submitted to scanning electron microscopy (SEM) coupled to energy dispersive spectroscopy analysis (EDS) to characterize the composition and microstructure. X-ray diffraction (XRD) was performed to determine the crystalline structure and energy dispersive X-ray fluorescence spectroscopy (EDX) was performed to determine the chemical composition and the homogeneity of the composite alloy.Artigo IPEN-doc 23717 A Study of Production of Tungsten Copper Alloy by Powder Metallurgy, Applied to Radioactive Shielding of Transport Equipment for Pharmaceutical Products2015 - CIONE, FRANCISCO C.; SOUZA, ARMANDO C. de; SENE, FRANK F.; RIZZUTTO, MARCIA de A.; ROSSI, JESUALDO L.Safety is of paramount importance for the storage and transportation of radiopharmaceutical products, being directly dependent on the radiation shielding material used in specific devices. The focus of present work, part of a larger project, is to minimize the use of harmful materials, as lead and depleted uranium, in such devices construction. The radioactive energy reduction varies according to density of material used as shielding. Because Tungsten has a high density and, implicitly, good shielding properties without to be harmful, but has poor workability, researches were focused on Tungsten - copper heavy alloys. The objective of the performed research was the optimization of alloy composition in order to achieve the best linear absorption coefficient. The studied compositions were 15, 20 and 25 wt.% copper. The linear absorption coefficient was similar either for the green and sintered compacts, thus the porosity level did not have measurable effect on the radiation attenuation.Resumo IPEN-doc 22086 Estudo da viscosidade de vidros niobofosfatos em função do teor de nióbio2007 - BARROS FILHO, ERALDO C.; MARTINELLI, JOSE R.; SENE, FRANK F.Artigo IPEN-doc 21034 The shielding against radiation produced by powder metallurgy with tungsten copper alloy applied on transport equipment for radio-pharmaceutical products2015 - CIONE, FRANCISCO C.; RIZZUTTO, MARCIA A.; SENE, FRANK F.; SOUZA, ARMANDO C. de; BETINI, EVANDRO G.; ROSSI, JESUALDO L.Artigo IPEN-doc 20790 Development of phosphate glass microspheres containing holmium for selective internal radiotherapy2014 - BARROS, E.C.; SENE, F.F.; MARTINELLI, J.R.Resumo IPEN-doc 20478 Avaliação da atividade e danos na superfície de microesferas de vidros fosfatos contendo hólmio após irradiação neutrônica2014 - BARROS FILHO, ERALDO C.; SENE, F.F.; MARTINELLI, J.R.Resumo IPEN-doc 20353 Desenvolvimento de vidros fosfatos contendo hólmio para aplicações em radioterapia internas seletiva2014 - BARROS FILHO, E.C.; SENE, F.F.; MARTINELLI, J.R.Resumo IPEN-doc 09317 Vidros a base de fosfato - uma revisao1999 - MARTINELLI, J.R.; SENE, F.F.Resumo IPEN-doc 19840 Desenvolvimento de microesferas de vidro fosfato contendo disprósio para aplicação em radioterapia interna seletiva2013 - BARROS FILHO, ERALDO C.; MARTINELLI, JOSE R.; SENE, FRANK F.