Effect of Cr₂O₃ Addition on Sintering Behavior of Novel Chromite‐Based Ladle Filler Sand

Abstract

Developing novel filler sands has garnered significant interest in improving the ladle’s free‐opening rate and enhancing the cleanliness of high‐Mn and high‐Al steel. Laboratory studies explored the effect of adding Cr2O3 powder on the sintering behavior of chromite‐based ladle filler sands. Furthermore, interfacial phenomena were examined between the sands and high‐Mn and high‐Al steel grades, varying in Mn contents. The results demonstrate that adding Cr2O3 power played a role in inhibiting the liquid phase formation in the filler sand. With a 16% addition, the steel (Mn mass%=30) reacted with the sand, leading to the shape of a spinel phase (SP), specifically (Mn, Fe, Mg)O·(Al, Cr)2O3, which facilitated the separation of the liquid phase. The reduction of FeO to Fe by Mn, Al, and C in steel, especially Al, was hindered by adding Cr2O3, resulting in a suitable sintering degree that ultimately benefited ladle free‐opening. SiO2 is crucial for forming the liquid phase during the sintering process. The SiO2 content of the sand should be about 20% to achieve optimal sintering effects. Chromite sand for casting is not suitable for the high‐Mn and high‐Al steels. The mixed sand composition presented in the current study demonstrates potential as a suitable filler sand material for high‐Mn and high‐Al (20 ≤ Mn mass% ≤ 30) steel.This article is protected by copyright. All rights reserved.