The Effect of Copper on Carbon Diffusivity in PremoMet® Alloy

Ultra-high strength low alloy (UHSLA) steels are used in many applications since they provide high strength and toughness at a lower cost than steels with higher alloying additions. The carbon diffusivity of a specific steel developed by Carpenter Technology, named PremoMet®, was studied using two different methods, both focusing on the effect of the copper composition. Carburization and chemical analysis was performed in order to directly measure carbon profiles and calculate diffusion coefficients, which were found to decrease to 0.5 wt.% copper and then increase. Atom Probe Tomography (APT) was performed on three different conditions, of which 0.5 wt.% copper had the least amount of carbon clustering. Low copper content showed longer clusters, whereas high copper content showed a significantly higher amount of smaller clusters. Diffusion coefficients and mechanical properties were compared to the carbon clustering and it was determined that copper does have an impact on the carbon diffusivity.M.S., Materials Science and Engineering -- Drexel University, 201