Grant: Alliance Grants

Canada is home to North America's largest vehicle production region and is one of the world's top 12 producers of light vehicles. Yet, Canada's transportation sector is responsible for 25% of the total greenhouse gas (GHG) emitted nationally. To reach net-zero GHG emissions by 2050, efforts in the automotive industry include reducing the weight of structural materials by replacing steel components with aluminum and lightweight composites. However, steel components are necessary for areas where strength is required (e.g., frames and structurally reinforced areas), and traditional high strength low alloy steels are being replaced with advanced high strength steels (AHSS). The improved strength of AHSS stems from their microstructure and alloy composition, which enables thinner (i.e., less) material to be used for the same part, ultimately decreasing the weight of the vehicle and increasing fuel efficiency. Unfortunately, AHSS alloys undergo rapid corrosion and do not meet industrial requirements currently. The goal of this partnership between ArcelorMittal Dofasco and Western University is to understand the corrosion mechanism of AHSS compared to conventional steels and identify key factors in reducing or accelerating the alloy's corrosion rate. This 2-year project will involve the investigation of the localized corrosion behaviour and mechanism of AHSS using a multiscale electrochemical approach. The electrochemical maps of corrosion rates will be correlated to the steels' microstructures and chemical composition to determine the initiation sites and mechanisms. The project outcomes will elucidate why AHSS corrodes at a higher rate in comparison to mild steel, while advancing the use of scanning electrochemical probe microscopy (SEPM) analytical tools to study corroding systems. This, in turn, will ultimately enable Canada to cultivate greener automotive production.