Investigation of formation of precipitates and solidification temperatures of ferritic stainless steels using differential scanning calorimetry and Thermo-Calc simulation

The phase transformations in unstabilized and stabilized ferritic stainless steels during solidification were studied using Thermo-Calc and differential scanning calorimetry (DSC). The solidus and liquidus temperatures of the Thermo-Calc simulations were compared to the liquidus and solidus temperatures measured with DSC. Thermo-Calc software revealed the precipitates of the ferritic stainless steels to be MnS, TiN, Ti₄C₂S₂, NbC, and Ti(C,N). Given the low volume fraction of precipitates, DSC could not be used to reveal the onset of precipitation. There was reasonable correlation between the liquidus and the solidus temperature, as calculated using Thermo-Calc and as measured using DSC. Generally, a higher niobium content resulted in a higher solidification temperature range.