Matt Gear is a former PhD candidate at the University of Queensland, who was part of a research team within the Steel Research Hub that focused on the high-speed manufacture of smooth thin new metal coatings. Working with BlueScope, his particular focus was to understand the effects of composition on the physical properties of coating alloys.
By way of background, BlueScope commercialised new coated steel products featuring a coating alloy containing 2% magnesium in 2013 (http://www.steel.com.au/products/coated-steel/zincalume-steel). This next generation version of the original ZINCALUME® steel product provides equivalent corrosion protection at reduced coating mass. There are many economic and environmental benefits to minimising the coating mass, such as lower energy consumption and raw materials usage.
The production of a thinner, smooth metallic coating on a steel substrate requires a comprehensive understanding of the physical properties of the liquid coating leading up to and including its solidification. The R&D challenge was to extend the current knowledge and data on the liquid alloy’s physical properties and its interfacial behaviours with the atmosphere and steel substrate. These all play a crucial role in coating formation.
Matt’s project has generated new fundamental knowledge of relevant liquid alloy properties, such as surface tension and liquid fluidity. It has also assisted in better understanding the solidification process through determining the relative liquidus and freezing ranges of the liquid alloys and the in-situ observation of microstructural evolution using the SPring-8 synchrotron, the world’s largest third-generation synchrotron radiation facility (http://www.spring8.or.jp/en/).
Through the data generated from his project, a change to the processing conditions has been proposed to improve the coating surface stability. In the medium-term, this will be assessed at BlueScope; while in the near-term, this new data will inform other related research projects within the Steel Research Hub, including the numerical simulation research activity dealing with optimisation of the coating mass control equipment.
Finishing up his PhD and soon to graduate, Matt has said the personal highlights for him have been the opportunity to collaborate with some of the best researchers and steel technologists in Australia due to being a part of the Hub, as well as the chance to travel to international conferences, universities and research centres.