Influences of Adding Aluminum on Inclusions in H13 Steel through P–ESR

Abstract

Reducing oxide inclusions’ number and size by aluminum deoxidization is an effective way for improving working life of high strength steel. For this purpose, during inert gas protection electro–slag remelting (P–ESR) process and H13 steel as electrodes, the deoxidizer being made of aluminum grains, iron powder and calcium fluoride powder mixture was added into slag pool with different addition rates. Results of experiment indicated that, by P–ESR remelting, oxygen content reduced from 0.0045 to 0.0010 with different aluminum addition rates. Based on the SEM and EDS analysis, inclusions transformed from CaO–MnO–SiO2–Al2O3 particles in electrode to pure Al2O3 particles, and number and size of particles modified obviously. Finally, action mechanism of the deoxidizer during P–ESR process was discussed by analysis results and thermodynamic calculation.