WA Branch Technical Meeting - 9 August 2021

WA Branch Technical Meeting - 9 August 2021 Curtin Corrosion Centre

Source: Prof Mariano Iannuzzi, Director, with staff and students

The Curtin Corrosion Centre has been conducting industry-directed research and education for 35 years. Professor Mariano Iannuzzi, who has been Director of the Centre since 2019, explained how its well-earned reputation as a trustworthy research partner for oil and gas businesses has enabled a rapid expansion over the past five years, to the point where the Centre now has 22 staff and 23 research students, as well as 14 research associates and three collaborators. Professor Iannuzzi went on to outline some of the clusters of world-class expertise for which the Centre is particularly noted, including microbially induced corrosion, corrosion under insulation, hydrogen sulfide and carbon dioxide corrosion, tribo-corrosion, stress corrosion and environmentally assisted cracking. The Centre has already established facilities to deal with research challenges from the emerging hydrogen economy and is diversifying into computational modelling, concrete corrosion, polymers, and additive manufacturing. Through its links to other Curtin University Centres, it has exceptional capability in failure analysis. The Centre operates like a not-for profit business. One stream is market-priced demand-driven research, with projects typically running less than 18 months. The other stream comprises longer term (e.g. five-year) partnerships between Curtin University and business groups. The partnerships fund longer-term PhD research and professorial appointments. Professor Iannuzzi then handed over to staff and students to provide some examples of current work. Sofia Hazarabedian described how her PhD research arose from an oil and gas industry problem with cracking of precipitation hardened Alloy 725 nickel-based alloy components, made from batches that had passed standard qualification tests of mechanical properties and microstructure. Using a suite of sophisticated analytical techniques, she identified the cause as grain boundary precipitation of an unusual intermetallic phase (F-phase), which depleted the adjacent alloy of cobalt and molybdenum. She also devised a simple objective cyclic polarisation test procedure, which can quantify the extent of F-phase precipitation. At the same time, this electrochemical test can serve as a preparatory step for metallographic evaluation, as it makes the precipitates more easily visible. These tests make it possible to screen batches of alloy and will help producers develop thermomechanical treatments to minimise the embrittlement. Dr Sheila Omar, one of the Centre’s Research Fellows, gave an example of shorter-term demand-driven research. She described a one-month project to determine whether corrosion treatments proposed for a mineral transport slurry pipeline were likely to be cost effective. Dr Omar described the four-step approach of: evaluating the literature; conducting a suite of corrosion tests that simulated operating conditions (water quality, bacterial populations); evaluating and communicating the results to a non-expert audience; making recommendations for action. The ten tests conducted simultaneously, without the proposed corrosion mitigations, showed that concerns about differences between the welds and the original steel were not justified, and that only one set of conditions involved the risk of pitting corrosion. Otherwise, without expensive treatments, the uniform corrosion could be managed for the designed life of the pipeline. Time restraints limited the inspection of the Centre to a small section of the extensive laboratory and testing facilities, along with a video presentation of the autoclave testing for hydrogen sulfide and mercury corrosion. One of the projects on view involved additive manufacture and subsequent mechanical testing of 316 stainless steel components. A technique under investigation is weight reduction by making components with internal lattice-like structures, which could not be produced by conventional forming methods. As several of the visitors were personally familiar with the problems being studied, the opportunity to meet the researchers generated insightful questions and answers, which were greatly appreciated.