Inclusions
Given a steel with 20 ppm O and 0.01%S. Vary the amount of Al and Ca at 1813 K and see which inclusions are formed, something you can examine using the TCS Metal Oxide Solutions Database (TCOX).
Figure 1: Calculated effect of formed inclusions in a steel with 20 ppm O with varied amounts of Al and Ca at 1813 K. C1A1, C1A2 and C1A6 are short for CaO.Al2O3, CaO.2Al2O3, CaO.6Al2O3.
Effect of Inclusion Composition of 18-8 Stainless Steel
The stability and composition of sulfides were investigated [1980Ono] at 1100 °C by varying the Mn concentration of the steel: Fe - 0.06% C - 0.6% Si - 0.2% S - 8.4% Ni - 18.2% Cr.
Reference
[1980Ono] K. Ono, T. Kohno, Effect of Inclusion Composition on Stability of Inclusions and Corrosion Resistance of 18-8 Stainless Steel. Denki-Seiko[Electric Furn. Steel]. 51, 122–131 (1980).