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This work has the objective to report some, among many subjects discussed in the 4a Conferência Nacional de Ciência, Tecnologia e Inovação (4a CNCTI), which occurred between May 26-28 of 2010 in Brasilia. Among the several conferences of the event schedule and personal contacts that, in the authors opinion, were considered relevant, are emphasized in this article: the new role of innovation on the context of science and technology; the importance of the institutions of science and technology on the innovation context; the progress and limitations of the regulatory mark and, at last, a new approach about the importance of intellectual property. The information and discussions here presented indicate that science, technology and innovation will assume a remarkable role in the economic and social development of Brazil in this decade. Source

de Vasconcellos P.I.G.,NUCLEP | Rosenthal R.,LAMAV CCT UENF | Paranhos R.P.R.,LAMAV CCT UENF
Soldagem e Inspecao | Year: 2010

The duplex and superduplex stainless steels have an austenitic-ferritic microstructure with an average fraction of each phase of approximately 50%. This duplex microstructure is responsible for the excellent mechanical properties, specially the yield strength and toughness, and for the improved pitting and stress corrosion cracking resistance in chloride environments. Welding of these steels is often a critical operation. In this work, a superduplex stainless steel SAF 2507 pipe was welded by the GTAW process in the root pass and by SMAW process on filler passes, and one pipe of duplex SAF 2205 was entirely welded by the GTAW process. The microstructure of the base metal, heat affected zone (HAZ) and weld metal was characterized and quantified. Toughness and corrosion resistance and chemical composition were evaluated and correlated. The results of impact Charpy-V tests were considered adequate. Precipitation of intermetallics, carbides and nitrides has not been observed. The best corrosion resistance results presented by the superduplex stainless steel welded joint, compared to the duplex steel, was attributed to the lower delta ferrite content in the weld metal and HAZ, and the weld metal chemical composition enriched in Cr, Mo, W and N. Source

de Almeida L.L.P.,LAMAV CCT UENF | Tatagiba L.C.S.,LAMAV CCT UENF | Rosenthal R.,LAMAV CCT UENF | Paranhos R.P.R.,LAMAV CCT UENF
Soldagem e Inspecao | Year: 2010

This work presents the evaluation of welded joints using ceramic backing made in the laboratory. The one-sided welding technique was used to weld A-36 steel plate with 6,4 and 15,8 mm thick by the GMAW process. With the 6,4 mm steel plate, only the root bead welded over the ceramic backing was evaluated. With the 15,8 mm steel plate, a multipass welded joint was made. After welding, the welded joints were submitted to visual inspection, dye penetrant, macrograph, Vickers micro hardness, optical microscopy, bending and tensile testing and chemical analysis by EDS. The results show that the root pass made over the ceramic backing, presented adequate good shape, free from discontinuities, with adequate penetration in the edges of the groove and adequate reinforcement. Concerning the welded joint, the microstructure of the fusion zone presented predominance of primary ferrite, consisting of grain boundary ferrite and polygonal ferrite, and ferrite with aligned second phase. The Vickers micro hardness obtained mean values below 180 HV both in the heat affected zone and the fusion zone. Bending tests did not show discontinuities greater than 3 mm and in the tensile tests the rupture occurred in the base metal, indicating that the welding procedure was adequate. The chemical composition of the inclusions both in the root pass as in the last weld bead have the same constituents, despite different proportions, indicating that there was not contamination of the ceramic backing material into the weld bead. Source

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