In the electric arc furnace (EAF) steelmaking process, refractories are subjected to multiple challenges such as arc radiation, molten steel scouring and sudden temperature changes. In the hearth bottom, hearth slope and molten bath areas, the traditional monolithic ramming process using magnesia is gradually being replaced by the precast magnesia-carbon brick masonry technology. Comparative data from actual operations show that the average service life of the former is 120–150 heats, while that of the latter can reach 200–250 heats. Despite the higher initial investment, the comprehensive maintenance cost is reduced by approximately 30%.

Protection of the hot spot zones and slag line zones is the key to the EAF refractory system. High-quality magnesia-carbon bricks exhibit excellent performance in these high-temperature, vulnerable zones through the combination of special antioxidants and microstructural design. Measured data from a steel plant indicate that the application of multi-layer composite-structured refractories in hot spot zones, combined with an enhanced cooling system, can reduce the local temperature by 150–200℃ and decrease the material loss rate by 35%.

In response to the special working conditions of ultra-high power (UHP) electric arc furnaces, differentiated solutions have been developed for refractory configuration. The permanent lining adopts high-purity magnesia to ensure fundamental stability; magnesia-chrome bricks containing 15–18% Cr₂O₃ are used for the furnace door side columns to resist mechanical impact; high-performance magnesia-carbon bricks are deployed in hot spot zones to withstand arc radiation; and high-alumina bricks or more advanced oxide-bonded silicon carbide brick systems are selected for the furnace roof.

Particularly noteworthy is the advancement in taphole filler technology. High-iron dolomite fillers achieve excellent self-leveling property and rapid sintering performance through the control of special particle size distribution and sintering characteristics. Practices in a steel plant demonstrate that the new-type fillers can shorten the taphole maintenance time by 40% while reducing the risk of secondary oxidation of molten steel.

Although the open hearth furnace steelmaking process is gradually being phased out, its performance requirements for refractories remain representative. In practical applications, refractories must meet four core performance indicators: refractoriness not less than 1790℃; slag corrosion resistance rate controlled below 15%; good thermal shock resistance (withstanding more than 20 water-cooling cycles at 1100℃); and room-temperature compressive strength reaching over 40 MPa.

Industry development trends show that low-carbon magnesia-carbon bricks (with carbon content < 12%) and nano-composite refractories will become the mainstream in the future. By introducing in-situ reinforcement technology and gradient design of microstructures, the new generation of materials can reduce carbon emissions by 25–30% while maintaining excellent service performance. The application of digital twin technology has further improved the accuracy of refractory service life prediction to over 85%.

Overall, refractories for steelmaking are moving towards the direction of high performance, functionalization and intelligence. The in-depth integration of material research and development with working condition simulation, and the widespread application of the whole-life cycle management concept will drive refractory technology to a new height, providing solid support for the green and efficient development of the steel industry.