Effects of rare earth modifying inclusions on the nucleation mechanism and mechanical properties of MC5 roller steel

Abstract

The effect of Ce treatment on the inclusions and mechanical properties of MC5 roller steel after solidification and annealing process was investigated. The implementation was observed by thermodynamic calculation, Electron Probe Micro-Analyzer and high-temperature confocal laser scanning microscopy (HT-CLSM). The results showed that as rare earth content increase, the inclusions were effectively modified into cerium oxide (Ce-O) and cerium sulfide (Ce-O-S); Compared with 0 RE steel, eliminating the proportion of inclusions larger than 5 μm by 14% and 22%; the average size decreased to 3.60 μm and 2.30 μm. Subsequently. CLSM was used to observe the aggregation, separation and agglomeration behavior of MgAlO4 inclusions and alloy elements on the surface of molten steel. Moreover. the ultimate tensile strength and yield strength of MC5 roller steel with Ce treatment increased by 12.6% and 34%. The addition of rare earths could improve the of MC5 roller steel, it provides effective reference value for subsequent industrial experiments.