Nonmetallic inclusions in low-carbon structural steel with titanium and cerium

1. Additions of titanium (0.02–0.05%) to low-carbon structural steel of the 15KhML type lead to a reduction of the fracture toughness by an average of 0.5 MJ/m2. This results from the formation of lamellar Ti(C, N) and manganese sulfide stringers. 2. Adding 0.06–0.08% Ce and raising the austenitizing temperature have positive effects on the fracture toughness of the steel containing titanium. Cerium promotes globularization of the sulfide phase, although it does not suppress the formation of Ti (C, N).