Industry Updates
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Industry Updates
Published online: 23 February 2007 Ó ASM International 2007
Argonne National Laboratory Alloys Resist Metal Dusting Degradation of structural components made from ironand nickel-base alloys by metal dusting occurs in a variety of high-temperature, high-carbon activity processes that are in widespread use in the chemical and petrochemical industries. Metal dusting is a corrosion phenomenon that occurs in these alloys and is characterized by pitting and mass wastage when exposed to strongly carburizing gas atmospheres in the temperature range of 400–800°C. To avoid metal dusting problems, industry is often forced to design lower temperature processes that are less energy efficient, waste more materials, and have lower yields. A study conducted at Argonne National Laboratory (under the temperature, pressure, and gas composition
conditions found in the reformer environment) has clearly established the role of carbon deposition in the mechanism leading to initiation and propagation of metal dusting attack and has lead to the development of metal dusting-resistant alloys. The development of the alloys will have positive impacts on a number of industries and enable significant energy savings. This technology was recently selected by the independent judging panel and editors of R&D Magazine as one of the 100 most technologically significant products introduced into the marketplace in 2006. For more information: Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439; tel: 630/ 252-2000; web: http://www.anl.gov/techtransfer/Awards/ rd100_short.html#dusting.
This macrograph compares commercial nickel-base Alloy 600 (left) and Argonne’s new alloy after 5,700 h of exposure to the same metal-dusting environment at 593°C. Photo courtesy of Argonne National Laboratory
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Answers Sought in Failure of Quebec Overpass As reported by the Canadian Press, three lanes of an overpass in Laval, Quebec, plus a pedestrian sidewalk, fell onto Highway 19 in September of 2006, killing five and injuring six others. Quebec Transportation Department officials hope that a series of bore holes drilled deep inside the concrete of the failed structure will help determine whether the span’s steel and concrete core was compromised by age, water infiltration, and corrosion. David Lau, a professor of civil engineering at Carleton University in Ottawa, said there are many contributing factors and the key is to identify the initial failure point and assess the condition of the steel rebar around that region. ‘‘The bridge stood for 35 some-odd years, so obviously it must have been something which took place over time,’’ said Walter Saltzberg of ISIS Canada Research Network, a University of Manitobabased center that provides civil engineers with better ways to build bridges. Published reports suggest an initial analysis of the overpass found that steel appeared to be ‘‘missing’’ from inside the concrete structure and that corrosion had been ruled out as a cause of the catastrophe. A conclusive report is due for completi
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