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Weathering steels, sometimes called "patinabili" in Italian language and more often known with the trade name COR-TEN™, are one of the possible options for designers in manufacturing of welded structures, for example of metal bridges, in consideration of the environmental conditions and in service performance. In this Review we have certainly considered these steels as structural materials, typically for the public or private buildings construction, not so much as a possible option for architectural functions. In the spirit of the new series of articles just dedicated to the architectural use of some specific building materials, in this issue we've considered the case of atmospheric corrosion resistant steels, presenting them not only from the structural point of view as well as from the architectural one, not forgetting obviously to briefly describe the properties that have made success. [ABSTRACT FROM AUTHOR]

The inner surface of pressure vessel steel used in the petrochemical industry is often coated with corrosion resistant materials. The industrial process that combines increased productivity with controlled dilution is ESSC (ElectroSlag Strip Cladding). The paper aims to overcome the current ESSC process limitations, analyzing the possible benefits introduced by Multi Strip technology, Twin type. The tests with combinations of carbon steel coated with Alloy 625 and Type 347 deposit on creep resistant low alloy steel were conducted. [ABSTRACT FROM AUTHOR]

Presently, many economical and technical efforts are made by pipeline industry aimed to satisfy the needs to transport gas from far away regions to the final market and to set new solutions in terms of both design criteria and new high performance materials. Due to the fact that easy Oil and Gas is largely exploited and new fields will be more and more in deeper water (it means water depths greater 305 m), that means higher pressures and temperatures and more corrosive environments, material requirements are increasing. In this situation low-alloy carbon steels tend to be structurally satisfactory, but lack in terms of corrosion resistance. On the other hand stainless steels and nickel alloys resist to corrosion environments but are lack in terms of strength or extremely costly. Clad pipes, low-alloy carbon steel with a thin layer of a corrosion-resistant alloy, is presently considered, more and more, a suitable solution to the most demanding requirements of strength, corrosion resistance and cost-effectiveness. In a cladded pipe, the (generally) unalloyed carbon steel outer pipe handles the internal and external pressure, while the high-alloy cladding provides the corrosion protection. The paper describes the pipes and fittings production starting from metallurgical clad plates. In particular the experience developed by Allied Group is described. The developed products and components represent the ideal candidate for the most severe offshore and subsea applications typical of the Oil&Gas sector. [ABSTRACT FROM AUTHOR]

This article is extract from the publication "Practical Guidelines for the Fabrication of Duplex Stainless Steels", first edition 2011, published by the International Molybdenum Association (IMOA). More in detail, the focus is on the Chapter 12 "Welding Duplex Stainless Steels", where the Authors present an updated overview concerning the most relevant issues, such as the differences existing in welding between the conventional austenitic stainless steels and the duplex ones, the selection and the fine tuning of the welding processes and the related procedures, the suggested joint preparations, the proper interpass temperature and heat input to set-up for getting a proper final phase balance, the selection of the filler material as a function of the base material and the expected weld performances. The article gives also a detailed analysis on the applicable non-arc welding and joining processes, without forgetting the post fabrication clean-up procedures, which are often critical for the performance of the welded product in service conditions, such as the corrosion resistence. The staff of Rivista Italiana della Saldatura is grateful to IMOA for the permission given to the publication of the Italian translation of this extract. [ABSTRACT FROM AUTHOR]

This paper describes both the mechanical and corrosion behaviour of similar made from AA2024 and AA6056, all in form of rolled sheet Friction Stir Welding (FSW) lap joints. The effects of heating using three different weld speeds, on both alloys employed in this work, were also investigated. Static mechanical tests were carried out providing infor-mation about static strengths and failure modes. Optical observation was used in investigating imicroscopically weld and welding defects. The corrosion behaviour of such joints was investigated by electrochemical dc techniques (open circuit potential -O.C.P. - monitoring and anodic polarization) using a cap-illary electrochemical cell, with a resolution of 0.5 mm. In order to confirm results obtained by local measure-ments, global gel visualization tests were also performed on the same specimens. The best mechanical and electrochemical performance was observed when the weld speed is low. In AA6056 fail-ure occurs in weld along the mixing area, while in the case of welding AA2024 it occurs mainly in the lower plate, most critical zone is the HAZ. [ABSTRACT FROM AUTHOR]