Modification of the inclusions in austenitic stainless steel by adding tellurium and zirconium

Abstract

The control of the formation of non-metallic inclusions and the characterization represents the basis for the improvement of steel product properties and leads to sustainable development in the design of new steel grades. In order to produce steels with better machinability, such as AISI 303 grades, a modification of inclusions with a carefully designed chemical composition is presented. The aim of the research was to examine the possibility of increasing the effect of machinability of AISI 303 stainless-steel micro-alloying by tellurium and zirconium. In this work we present detailed SEM/EDS analyses of the modified non-metallic inclusions - manganese sulphides. In AISI 303 steel alloyed with Te and Zr the inclusions consisted of complex particles with more spherical shapes effectively acting as shaving breakers. For this reason the AISI 303 modified grades have better machinability compared to the standard AISI 303 grade and with mechanical properties within the limits prescribed for AISI 303 standard grade.