This article presents the results obtained at 16 tropical test sites participating in the “Ibero-American Map of Atmospheric Corrosiveness” (MICAT), a project on atmospheric corrosion carried out during the period 1988–1994 at some 70 test sites distributed across 12 countries of the Latin-American region, Spain and Portugal. The tropical climate and its different climatic variants are characterized by high average air temperatures, with considerable daily thermal fluctuations, high average relative humidity, and generally high precipitation volumes. The work is structured in three main blocks: apparently unpolluted atmospheres (i), and marine atmospheres, differentiating between pure marine atmospheres (ii) and those in which both chloride (Cl-) and sulfur dioxide (SO2) pollutants coexist (iii). In each block an attempt was made to determine the role of the tropical climate in the magnitude of corrosion attack shown by four typical reference metals (mild steel, zinc, copper and aluminum) exposed for one-year periods in tropical atmospheric exposure conditions.

In this work five paint systems applied on steel, all of them including a zinc rich primer in their composition and recommended for atmospheres with very high corrosivity (C5 category), were studied. Epoxy intermediates, acrylic water-borne, polysiloxane, aliphatic polyurethane and acrylic polyurethane topcoats were included. Water condensation, neutral salt spray and chemical resistance tests, according to EN ISO 12944-6, were performed. The purpose of chemical resistance test is to assess the ability of a system to withstand high industrial environments. Therefore, paint adhesion before and after artificial ageing was evaluated. Visual inspections were carried out. Generally, the best results were obtained for the systems with polyurethane based topcoats. However, changes in the formulation of one of the two environmentally-friendly systems under study that allow an increase of its adhesion, can probably increase its suitability for use in marine atmospheres with C5 corrosivity.

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Telecommunication systems are currently facing numerous technical and economic problems due to corrosion. Interface equipment (outdoor cross connection cabinets) includes the connection modules and their over-voltage protection magazines. These modules contain the connection terminals, which are permanently subjected to a direct voltage of 50 V and to a wide thermal range, with the consequent hot-house effect and corrosion, phenomenon that can lead to functionality problems. The connection terminals are made of brass coated with nickel and silver. One module contains 20 pairs of terminals. Each pair consists of two lead/terminal contacts in series. The resistance across each pair has been measured and from this value the lead/terminal contact resistance was deduced. Scanning Electron Microscopy with associated Energy X-Ray Dispersive Spectrometry (SEM/EDS) and X-Ray Diffraction (XRD) were used for morphological and chemical evaluation. With this work it was possible to characterize the connection terminals and to evaluate the formed corrosion products in laboratory and in real exposure conditions. Analysis and treatment of obtained data allowed to conceive and to propose a simple model to explain the observed evolution of the contact resistances during artificial ageing in cabinet. All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications Ltd, www.scientific.net. (Scite.

The development of new structural applications for the unidirectional pultruded glass-fiber and carbon-fiber reinforced plastic rod, needs the transmission of a considerable tension load to the composite rod, without local damage at the end of the rod.For this purposes we have developed a new kind of metallic end bonded insert, with easy assemblage to the composite rod. These minimises stress concentrations, allowing a good transfer of tensions loads without premature failure of the rod.The methodology behind the development of these metallic inserts is explained with experimental and numerical data verifying the improvements.All rights reserved. No part of contents of this paper may be reproduced or transmitted in any form or by any means without the written permission of Trans Tech Publications Ltd, www.scientific.net. (Scite.