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The IIW White Paper is a booklet produced by a panel of 80 experts of the IIW, aimed at providing reader with a picture on welding and allied technologies dated 2012, but mainly focused on the challenges and direction of these technologies for the next 20 years. Statistical data on value added by welding and welding related occupation are included in the first part, while the main content is devoted to evaluating technologies, processes, materials, inspection and testing techniques, standard and codes which can potentially become state of the art in the next years. A section is also devoted to identify those changes in the industrial world that can impress a driving force to welding and allied technologies. The article is a non-exhaustive resume of the IIW White Paper, while the full document is available for free on the IIW website (www.iiwelding.org). [ABSTRACT FROM AUTHOR]

For dissimilar metal welds, between austenitic stainless steels and ferritic steels, an austenitic stainless steel filler material with an adequate composition is normally used. To minimize the risk of hot cracking, the weld zone should preferably be constituted by an austenitic microstructure with a small amount of ferrite δ. During solidification, the microstructures depend on filler material and base material compositions. Useful indications of the weld zone microstructures can be drawn from such diagrams, for example the Schaeffler diagram, which defines the fields of existence of the phases as a function of composition expressed in terms of chromium equivalent (Creq%) and nickel equivalent (Nieq%). Recently alternative diagrams to Schaeffler diagram have been proposed. An amendment was introduced in one of these diagrams to better characterize the boundary area between martensitic-austenitic structure and fully austenitic structure. In this paper, by means of the experimental test results of austenitic stainless steel and ferritic steel joints, welded with laser beam process, some specimens were obtained with a weld zone composition near to the boundary between martensitic and austenitic zone in the Schaeffler diagram. The content of the elements was calculated by energy dispersive microanalysis (EDS). The microstructures were examined by optical microscopy and scanning electron microscopy (SEM) and by Vickers microhardness tests. For some microstructures, which were fully austenitic, the position of the corresponding points were located in the martensitic-austenitic zone below the line defined by the original Schaeffler diagram, while they were in accordance with the new definition of the boundary zone of the modified Schaeffler diagram. [ABSTRACT FROM AUTHOR]

In this paper the development of a welding procedure for the joining of steel type UNS S32760 (Super duplex F55) for use in the off-shore application is described. The joint was realized by means of the TIG (GTAW) manual process for the first passes and by a manual filling process with stick electrode (SMAW), in order to obtain the combination of mechanical and microstructural characteristics desired by the customer. The results obtained from the tests on the joints must provide proof of successful completion of all the tests to be part of the joint in accordance with the contractual requirements and stabilized the base for actual use in the production. The particularity of the case, in addition obviously to the inherent difficulties posed by the type of steel chosen, consisted in the request by the customer of a combination of mechanical and microstructural characteristics to the limit of the possibilities of a welding procedure suitable for use in production mode and times compatible with the internal market and production requirements. It was therefore necessary to design the welding procedure and choose the most suitable process parameters to achieve the required results. The evaluation of the joints to achieve in production and the characteristics to be obtained, has led to decide to perform welding with welding processes previously mentioned and in the welding position-frontal plane (PB/2G). The main problems to be considered in the design phase of the welding procedure, are to be found in the value of the maximum heat input, interval of interpass temperatures to be observed and the type of shielding gas to use with which material can be welded to avoid the formation of intermetallic microstructure phases of the joint and sappers of corrosion resistance. [ABSTRACT FROM AUTHOR]

This article offers information on the beginning and the development in Italy and abroad of technical assistance activities performed by IIS and later on by IIS Service srl. At the purpose, three subsequent periods are considered: a first one of affirmation of such activities; an intermediate one of consolidation of IIS on the market and of beginning of organization of its structure; a final one of further growth of such activities and of development and completion of IIS restructuring in order to prepare the partition which originated the IIS Group. The latter comprehends IIS Ente Morale (no profit distributing society), IIS Cert srl (Ltd) and IIS Service srl (Ltd), established at the beginning of 2011, and IIS Progress srl (Ltd), established at the beginning of 2013. In particular, the paper shows how, in some sixty years of activity, IIS gained a fame of seriousness, reliability and competence, that have made it one of the most comprehensive benchmarks in the field of welding, allied processes and connected techniques, appreciated everywhere it acted, in Italy, in Europe and in other continents. Finally, it is remembered that in 1988 IIS acquired with its own resources a modern and well-equipped headquarters in Genoa, that, in mid-2013, IIS Group owned various other regional offices and that at the time had in force some 225 employees (including some sixty graduate engineers and some one hundred technical licentiates), about half of whom are employees and managers of IIS Service srl. [ABSTRACT FROM AUTHOR]