The Effect of CeO2 and Hf Additives as a Grain Refinement on the ‎Microstructure and Hardness of Austenitic Manganese Steel

The fine-graining process by applying heat treatment methods. cannot be effectively applied to austenitic single-phase steels, including Hadfield steels, Other grain refining methods, such as thermomechanical methods, need more energy, cost, and more environmental consequences. In this paper, REM-based inoculations (Rare Earth Metals) and specifically CeO2 and Hf with values of 0, 0.05, and 0.1 wt% of CeO2, as well as 0 and 0.05 wt% of Hf, were added into an austenitic high Mn Hadfield cast steel. The results showed the effect of inoculation amount on austenite grain size, segregation, reduction of shrinkage microporosity, pearlite layer spacing, and increase in hardness of these steels despite small changes in mechanical properties. Changes in the amount of hardness in inoculated steels compared to base steels led to an increase of 80.95% in the as-cast condition, which is a particularly important feature due to the need for high anti-wear properties in these steels.