Grant: Alliance Grants

Automakers increasingly turn to advanced high strength steel (AHSS) alloys for light-weighting, the single most effective way to improve the efficiency of fossil-fueled cars and the range of electric vehicles. It is crucial to protect these thinner-gauge parts from corrosion; this is often done through continuous galvanizing, in which a steel strip is coated with a protective zinc layer, or galvannealing, in which the zinc-coated strip undergoes a subsequent heating step to form a Zn-Fe intermetallic layer that offers superior corrosion, weldability, and paint-adhesion. Unfortunately, steelmakers incur high scrap rates due to substandard properties that, in many cases, can be traced to thermal excursions caused by uncertain variations in the radiative properties. These costs impact the entire Canadian automotive chain, from resource providers like Teck Metals, to steelmakers like Stelco and Arcelor-Mattel Dofasco, automotive parts suppliers like Magna, original equipment manufacturers like Ford and General Motors, and ultimately to consumers. The objective of this 3.5-year research project is to develop radiometric techniques to improve control of the galvanneal process. The academic team at the University of Waterloo and McMaster University, will work closely with Stelco, Teck, and Williamson, the key provider of industrial pyrometers to the North American steel industry, to connect the evolving surface state of the galvanneal to radiometric properties, and then incorporate this information into Bayesian pyrometry algorithms to provide temperature estimates and associated uncertainties. The project will conclude with an industrial proof-of-concept implementation on Stelco's galvanneal line. While the fmain focus is on improved thermal control, the radiative properties themselves will provide unique and heretofore unleveraged information about the kinetic and transport processes responsible for the coating transformation. Finally, at least three highly-qualified personnel will be equipped with job-ready skills in high demand by Canada's manufacturing sector.