Abstract: The sulfide in the industrial production of 46MnVS non-quenched and tempered steel slab containing tellurium was taken as the research object, combined with the inclusion three-dimensional etching and scanning electron microscope, the changes of sulfide equivalent diameter, quantitative density and three-dimensional morphology in the slab were observed and analyzed, and the influence of tellurium on sulfur segregation and sulfide distribution was summarized. It was found that the equivalent diameter of sulfide from quench layer to mixed crystal zone of tellurium modified slab  from 2.6 μm gradually increased to 5.8 μm. The effective diameter of sulfides in the central equiaxed zone first decreased and then increased, and the proportion of ellipsoidal and octahedral sulfides from edge to center gradually decreased from 84.2 % to 25.7 %. Compared with the unmodified slab, the sulfur segregation index decreased after tellurium modification,and the maximum sulfur segregation index decreased from 1.13 to 1.06. The equivalent diameter of sulfides decreased, the proportion of ellipsoidal and octahedral sulfides in the slab increased, and the proportion in the quench layer increased the most.

Key words: 46MnVS steel, tellurium modification, sulfur segregation, sulfide distribution