• Traditional CaO–SiO₂ mold fluxes are ineffective for high-Ti steel casting due to persistent steel–slag reactions that degrade flux properties and cause surface defects.
• Novel CaO–Al₂O₃-based low- or non-reactive fluxes with additives like TiO₂, BaO, and B₂O₃ can stabilize viscosity, enhance heat transfer, and control crystallization.
• Fluorine-free alternatives (TiO₂, B₂O₃, BaO, Li₂O, Na₂O) replace CaF₂, reducing environmental impact while maintaining similar lubrication and crystallization performance.
• Future research must optimize flux compositions for specific steel grades and achieve a balance between lubrication and heat transfer to minimize casting problems and slab defects.