Abstract: Zirconia ladle filter sand was prepared using zircon sand，chromite，and quartz sand as
the main raw materials. The sand meets the requirements for high alloy steel smelting in EAF ladle.
The influence of quartz sand content on its composition，structure，and properties has been studied.
The research results indicate that after high-temperature heat treatment，the linear change rate of
the sample gradually increases with the increase of the content of quartz sand，the apparent porosity
significantly decreases，and the bulk density first decreases and then increases. The particles in
each sample are mainly in point contact，forming generating a low melting phase dominated by
K2O-Al2O3-SiO2-FeO. Meanwhile，the high-temperature compressive strength slightly increases，
and the thickness of the sintered layer increases，promoting the sintering of the ladle filter sand.
For ladles for the smelting of high alloy steel grades in Baosteel's EAF（with an alloy content
of Cr + Ni + Mo ≥ 8%），the zirconia ladle filter sand has been applied to replace the chrome
ladle filter sand. Currently，it has been stably used for 9 months（a total of 210 heats），and the
automatic opening rate of the ladle has significantly improved，increasing from 85.0% to 97.2%.

Key words: Ladle filer sand, Zirconia ladle filter sand, High alloy steel smelting, Ladle automatic
opening rate