Effect of Ce₂O₃ on the Melt Structure and Properties of CaO–Al₂O₃-based Slag

Abstract

The low-reactive tundish flux is urgently required for the smelting of rare-earth steels. The effect of Ce 2 O 3 content on the properties (melting point and viscosity) and structure of CaO-Al 2 O 3 -Ce 2 O 3 -MgO-SiO 2 slag were analyzed in the present investigation. The research results indicated that the polymerized Q Al 4 and Q Al 3 units were modified to Q Al 2 units in aluminate, and the depolymerization of SiO 4 -tetrahedrons from Q Si 1 to Q Si 0 units with Ce 2 O 3 addition increasing from 5 wt% to 20 wt%. In addition, when the Ce 2 O 3 addition increased from 15 wt% to 20 wt%, the increasing area fraction in AlO 6 -octahedral units further led to a decrease in the degree of polymerization (DOP) in the melts. When the Ce 2 O 3 addition increased from 5 wt% to 20 wt%, the melting temperature decreased from 1 320°C to 1 301°C. Additionally, the softening temperature and the fluidity temperature also decreased 20°C and 24°C, respectively. The viscosity decreased as the Ce 2 O 3 addition increased from 5 wt% to 20 wt%, which was attributed to the decreased DOP and the increased superheat. A reasonable content for Ce 2 O 3 should not be excess 10 wt% in the current slag.

Melting and Crystallization Behaviors of Mold Flux with the Addition of Waste Electrolyte

“…In addition, the melting temperatures from previous studies, conducted by Zheng et al, [ 30 ] Ou et al, [ 31 ] and Marschall et al, [ 32 ] are also shown in Figure 5. It can be seen that both initial melting temperature and complete melting temperature of these new mold fluxes with waste electrolyte in this study are generally close to those commercial mold flux.…”

Effects of Mineral Raw Materials on Melting and Crystalline Properties of Mold Flux and Mineralogical Structures of Flux Film for Casting Peritectic Steel Slab

“…It is very important to choose the appropriate melting point of mold flux, which has great influence on the efficiency of the continuous casting process. When the melting point of the mold flux is too large, the liquid flux layer may be too thin, and the steel leakage accident may occur [20][21][22][23] . The melting point of the mold flux can be changed by adjusting the type and content of mineral raw materials.…”

Insight into Interaction Behavior of CeAlO3 Substrate and CaO‐Al2O3‐Based Slag

“…The radius of the diffusing species is listed in Table 4 . [ 17,18,34,35 ] The diffusion coefficient calculated based on Equation (4) is also listed in Table 4.…”

“…A similar method was reported in our previous reports. [ 16–18 ] The samples were melted at 1550 °C for 2 h to reach homogenization, and then the samples were quenched with ice water rapidly to obtain the glassy phase. Finally, the premelted slag (about 1.5 g) was mixed with alcohol as the binder in an agate mortar and then pressed into a cube sample (5 mm× 5 mm × 5 mm) under a load of 5 MPa for 5 min.…”

“…To reduce the slag‐steel reaction of rare earth steel, the authors designed the CaO‐Al 2 O 3 ‐Ce 2 O 3 ‐based slag. [ 16–18 ] Therefore, the dissolution mechanism of CeAlO 3 in the CaO‐Al 2 O 3 ‐Ce 2 O 3 ‐based slag was investigated at 1550 °C in the current study. The effect of w (CaO)/ w (Al 2 O 3 ) on dissolution behavior was discussed.…”