The Future of Steel

Research collaboration improves consistency of thin coatings for BlueScope products

Researchers from the University of Wollongong-led ARC Steel Research Hub, who are engaged with industrial counterparts to solve complex problems, have delivered a mathematical model to help steel manufacturers produce consistent and high-quality coated steel products.

Coated steel products such as corrosion resistant metallic alloy coated steels are important for BlueScope and other Australian steel manufacturers, particularly in building applications that must withstand the demands of the harsh Australian climate for extended periods.

The metallic alloy coating is applied to the steel strip by first passing the strip through a molten alloy bath, such as in hot-dip galvanising; then, as the strip passes out of the bath, a series of tiny air jets blow or ‘wipe’ away the excess coating material to achieve the desired coating thickness and uniformity.

While the process sounds simple, getting the system tuned correctly involves understanding and predicting the effects of several process variables, such as the speed of the steel strip, the pressure of the air jets and the coating material itself.

This poses a constant challenge for steelmakers in delivering high-quality coated products that meet product specifications and requirements.

Associate Professor Buyung Kosasih, a Chief Investigator within the Steel Research Hub, from UOW’s Faculty of Engineering and Information Sciences (EIS), said the joint UOW-BlueScope-University of Queensland research team had developed a mathematical model that enables the prediction of the coating response under different operating conditions.

“This represents a key modelling tool for BlueScope operational personnel to produce quality coatings,” he said.

“The mathematical model is the first that links the jet instability to potential coating surface defects.”

Based on the simulation results, plant trials have been proposed. Professor Kosasih said the outcome was a result of the fruitful collaboration and engagement between industry personnel and researchers.

“By closely working within a collaborative team comprised of industry, and researchers from multidisciplinary backgrounds, we can approach the challenges from multiple angles and provide skills that BlueScope does not currently have in-house, such as advanced modelling and experimental techniques,” he said.

“As researchers, we benefit significantly from such engagement.

“First, the opportunity to carry-out fundamental research, in this case, modelling the stability of impinging planar jet and thin-coating film, which is close to real-world application; and second, the opportunity to build relationships with industry via routine face-to-face discussions.”

The Steel Research Hub is one of the Australian Research Council’s Industrial Transformation Research hubs, jointly funded with BlueScope and supported by five other industry partners. It is an initiative that began in 2015, with $13.5 million cash and $12 million in-kind contributions over five years.

BlueScope Process Development Leader Wayne Renshaw said: “The Steel Research Hub provides ready access to researchers with advanced skill sets, a deeper understanding of the scientific fundamentals and a different way of thinking.

“This, along with a willingness to understand the specifics of the industry challenge and genuinely collaborate, is proving valuable.”

The Hub’s vision is to bring together teams of internationally recognised research and industry talent which deliver innovative solutions and breakthrough technologies in manufacturing and product development, helping to ensure sustainable growth in the Australian steel industry.