Davis Loen – 2019 Steel Internship Scholar
My time at SSAB Iowa was spent learning about the processes and challenges associated with mini-mill steelmaking to produce flat rolled heavy plate and coil products. My duties included inspecting steel slab internal structure, testing plate mechanical properties and keeping record of product quality checked throughout the mill.
The facility I worked in recycles scrap steel by melting it in an electric arc furnace, where it is refined and alloyed in a liquid state before the steel is continuously cast into slabs. These slabs are rolled into plates and coils. My responsibilities included assessing the internal structure of the steel in the as-cast condition. This assessment provided feedback for the casting process, to identify possible equipment issues and improve casting parameters. This assessment can also predict defects that could occur during the rolling process. Through this process, I have learned some of the common defects seen in continuous slab casting and the rolling of plate and coil. I enjoyed learning how many variables need to be controlled throughout the steelmaking process. For example, I was especially intrigued by how steelmaking practices depend on the season and weather conditions.
Lots of my time is spent in the physical testing lab, where I test plate and coil tensile samples for strength and ductility properties, as well as impact toughness through Charpy impact testing. These tests are to determine if the rolled product has the properties to meet a grade specified by a customer. These testing experiences bring physical meaning to the relationship between cast steel composition, rolling conditions, and product specification and application. I now have a full appreciation for the testing of steel used to make bridges and roller coasters.
I was also responsible for updating documents that track properties of rolled plate, such as internal structure and dimensional tolerances. This allows tracking of specific defect trends for product over periods of years. This has made me aware of the wide array of inspection methods that are used to assess plate quality, and the importance of effective documentation.
Possibly my favorite part of this experience was the people I have been lucky enough to work with. This includes other students who share my passion for metallurgy, laboratory personnel who have helped train me to safely operate machinery, the experienced metallurgists who happily provided technical explanations for steelmaking processes and answered all of my questions, and finally my boss who has put me in a position to learn as much as I could about steelmaking during my time there.