Nozzle clogging is a prevalent issue in continuous casting. It not only disrupts casting stability but escalates into nozzle blockage in severe case, resulting in decreased production efficiency and slab quality deterioration. The composition and structure of clogging deposits for typical steel grades were summarized. The mechanisms of submerged entry nozzle clogging were reviewed from three aspects: the physical adhesion of inclusions, chemical reactions in steel-refractory system, and the temperature drop resulted from the insufficient preheating.Chemical reactions were emphasized, including decarburization reactions, interactions between molten steel and refractory, and reoxidation reactions. Additionally,the discussion extended to numerical simulation studies in regard to nozzle clogging, mainly including flow field simulations and model of inclusion motion. Finally, the prevention strategies against nozzle clogging were discussed: the cleanliness improvement of steel, the argon blowing technique,the optimization of SEN parameters, and the external electric field and magnetic field treatment.

With the development of the times, the traditional high manganese steel is difficult to meet today's needs in terms of mechanical properties, hardness and even wear resistance and corrosion resistance. Improving the mechanical properties and corrosion resistance of high manganese steel through nitrogen alloying to extend the service life of steel, and the preparation of nitrogen-containing high manganese steel with excellent performance and stability is a trend of today's development.The influence of nitrogen on the alloying of high manganese steel, the influence of the smelting process,casting process and heat treatment on nitrogen-containing high manganese steel were described in this article.Finally, the future development direction of high manganese steel was discussed and summarized.

Based on the actual experimental data of a 210 t converter in a steel enterprise in Shandong Province, the impact of introducing CO₂ into the converter steelmaking process on smelting performance and carbon emissions was explored. The results indicate that the CO₂ injection process can effectively improve the dephosphorization rate of the converter, reduce the end-point carbon oxygen product, increase the recovery and calorific value of the converter gas, and significantly optimize the resource utilization efficiency. And it effectively reduces the generation of solid waste. In terms of carbon reduction, compared with conventional processes, the converter CO₂ top and bottom combined blowing process reduces the carbon emissions per ton of steel by 8.5% to 11.6%. The CO₂ top and bottom combined blowing steelmaking process not only improved smelting efficiency and economic benefits, but also had significant advantages in low-carbon transformation, providing an effective path for the steel industry to achieve green development.

The melting process of the scrap into the low carbon melting pool is difficult to predict, and it is impossible to realize a good control of the continuous charging process in electric arc furnace (EAF). Based on the principles of heat transfer and energy balance, a coupled model of scrap-melt pool-energy was developed. Through verification with experimental data, it was proven that the model could accurately quantify the melting process of single scrap steel and visualize the characteristics of scrap and molten pool under external energy input conditions. The results show that, for spherical scrap, the results of the model are close to the experimental results. For cylindrical scrap with diameters of 50.8, 63.6 and 76.2 mm, it is necessary to multiply the modification parameter for the immersion time in the model results (1.4, 1.3 and 1.2, respectively). On the other hand, higher energy intensity is beneficial to increase the melting speed of the scrap. In the case of insufficient energy input, the increase of melt pool steel volume is favorable for scrap melting, while in the case of sufficient energy input, the increase of melt pool steel volume is unfavorable for scrap melting.

The technical pathway of scrap steel into ladle during the LF refining process within long-process steelmaking to reduce hot metal consumption and its impact on the steelmaking process were studied. The results show that increasing the amount of scrap steel added to 150 kg/t can reduce the consumption of hot metal by 10% to 15%, while decreasing CO₂ emissions per ton of steel by 11.0%. However, the addition of scrap steel also brings a series of challenges. For every 50 kg/t increase in scrap steel, the nitrogen mass fraction of the molten steel increases by (3～5)×10^-6, and the total oxygen and hydrogen content also increase synchronously. The number and rating of inclusions in molten steel also increase，and power, electrode, and ladle refractory consumption significantly rise. Through thermodynamic and kinetic studies on scrap steel melting, quality standards of scrap steel for LF were established, and a method of preheating to 500～1 000 ℃ was proposed. By combining the improvement of heating efficiency, control of scrap steel particle size, and strengthening argon stirring, the melting time of scrap steel was shortened and the fluctuation of composition was reduced, the better economic and social benefits had achieved. Based on the synergistic improvement of calcium treatment and soft blowing process, the morphology and distribution of inclusions was improved, the purity of molten steel was enhanced, and the mechanical properties of steel had not been affected.

The stability and consistency of the continuous casting slabs are critical issues for the three-strand continuous casting with an irregular tundish. The mathematical model for the calculation of the RTD curve with the an irregular tundish, the flow and temperature fields of the irregular tundishes using argon blowing through gas curtain wall and with flow control device was established by coupling the standard k-ε model, DPM, mass and heat transfer models. Numerical simulations were used to investigate the effects of different flow control measures on the consistency of flow, RTD characteristics and temperature among three outlets of an irregular tundish by comparing the prototype tundish, gas curtain wall tundish and V-shape perforated baffle tundish. The flow velocity distribution of cloud maps and vector diagrams, and the distribution of tracer were ranked in superior sequence as baffle tundish, gas curtain wall tundish and prototype tundish. For the prototype, gas curtain wall and baffle tundishes, from the calculation results of RTD curves,the average residence times were 692.8, 673.1, 725.2 s; the dead region fractions were 20.4%,24.8%,14.9%; the peak value standard deviations were 1.97,1.19,0.266; and the average inlet-outlet temperature differences were 11.32,14.10,10.81 K, respectively. Therefore, the V-shape perforated baffle tundish is better than the prototype tundish and gas curtain wall tundish, which is conducive to the removal of inclusions and slab quality consistency of the three strands.

During the continuous casting of molten steel, issues such as nozzle clogging, equipment failures, or insufficient steel supply may necessitate blocking flow or fewer strands casting operations in the tundish. Taking a certain steel plant's four-strand T-shaped billet tundish as the research object, a combination of physical simulation and numerical simulation was used to analyze variations in flow field, temperature distribution, and inclusion removal efficiency before and after blockage. Through systematic analysis, an optimized blockage strategy tailored to this tundish was identified, along with measures to enhance flow consistency post-clogging by increasing casting speed. The results demonstrate that blockage operations induce significant alterations in molten steel flow dynamics, characterized by a decline in average temperature within the casting zone and compromised flow uniformity. Notably, blocking the central nozzle exhibits a lesser impact on the flow field compared to blocking side nozzles. Under this condition, the tundish exhibits a dead zone proportion of 15%, a maximum temperature difference of 3 ℃ in the casting zone, and improved removal rates for inclusions across all particle sizes relative to normal casting operations. Furthermore, elevating the casting speed on the blocked side accelerates steel flow, reducing dead zone proportion, narrowing the standard deviation of stagnation time, and promoting more uniform temperature distribution. This research offers actionable insights for optimizing blockage/reduced-flow operations in similar four-strand T-shaped tundishes.

The flow field and temperature field of induction heating tundish for large round bloom in a special steel plant were numerically simulated. The purpose is to reveal the transmission law of flow field and temperature field in tundish, and to guide the production and optimize the process of channel induction heating tundish. The results show that the average residence time of molten steel after induction heating in tundish is 40 s higher than that before heating, and the average dead zone volume is 3.3 percentage points lower than that before heating. The flow field of tundish is more stable after induction heating. Through the analysis of the transient temperature field and flow field, it can be found that the temperature field after induction heating is relatively stable as a whole, the temperature at each level is uniform, the disturbance in the tundish is small, the speed is slow, and there is no obvious eddy current phenomenon, indicating that it will not cause slag entrapment. The larger the excitation current is, the more obvious the induction heating effect is. By designing a reasonable power supply gear, low superheat constant temperature casting can be achieved.

In the continuous casting process for producing automobile exposed panel, ladle exchange can have significant impact on the distribution of large size inclusions in the continuous casting slabs. In the present work, the automatic analysis of inclusions and large sample electrolysis methods were used to study the distribution of micro size inclusions and large size inclusions in a 23 m long continuous casting slab produced in ladle exchange process. The results indicate that the ladle exchange has a certain impact on the number density of micrometer sized inclusions larger than 5 μm, but has little effect on the size distribution of micrometer sized inclusions. The ladle exchange has the significant effect on the inclusions larger than 30 μm, with an affected length of 13 m, including 3 m before and 10 m after the second heat starts pouring. The total content and number of large inclusions in the transition slab are much higher than those in the normal slab. The contents index of the inclusions with the sizes of 30－100 μm, >100－200 μm, and greater than 200 μm in the transition slab are 3 times, 1.2 times, and 2.5 times those of the normal slab, respectively. Their numbers index are 4 times, 1.8 times, and 3 times those of normal slab, respectively. The impact of lade exchange on large inclusions in the transition slab can provide reference for determining the length of the transition slab and improving the continuous casting process. 

This study focuses on the effective control of inclusions in molten steel during the continuous casting of silicon steel through the optimization of tundish covering flux. Using FactSage thermodynamic software, simulations were conducted to analyze the variations in liquid slag and inclusion content under different types, ratios, and compositions of tundish covering flux, as well as their effects on oxygen and aluminum levels in the steel. The computational results demonstrate that compared to the FG-13 type, the application of FG-5 tundish covering flux increases the liquid slag content by 0.083 4 g per 100 g of steel while reducing oxide inclusions by 0.060 57 g per 100 g of steel. At the ratio of covering flux to steel is 1∶100, the average liquid phase area is 0.16 percentage points higher than that at 1.5∶100 and 0.58 percentage points higher than at 2∶100, indicating improved slag fluidity and enhanced impurity absorption capacity. Industrial trials validated the optimized formulation, showing a significant reduction of 10.9 percentage points in Al-containing inclusions in steel samples.

The morphologies, quantities, sizes, and composition changes of inclusions in two heats of Q195L steel with different oxygen and sulfur contents (G85 and G86) were compared and analyzed for the samples of the converter end, the inlet and outlet of the argon station, the tundish, and the continuous casting slab. Combined with thermodynamic calculations and analysis of the compositions of steel and slag samples, the evolution law of inclusions was studied. The results indicate that the Q195L steel mainly contains Al₂O₃ inclusions, MnS inclusions, and Al₂O₃+MnS composite inclusions, which is consistent with the thermodynamic calculation results. The number density of Al₂O₃ inclusions with a diameter greater than 5 μm increases significantly from the converter end to the inlet of the argon station. This is because high-purity aluminum blocks are added for deoxidation during the converter tapping process. The oxygen content in steel mainly affects the content of large-size inclusions. The O element content in the tundish of G85 heat is higher than that of G86 heat, resulting in a significantly higher content of Al₂O₃ inclusions greater than 5 μm compared to G86 heat. The sulfur content in steel mainly affects the content of fine MnS inclusions. After the inlet of the argon station, the S element content in the molten steel of G85 heat is lower than that of G86 heat, resulting in the content of MnS inclusions greater than 0.2 μm lower than that of G86 heat. The research results provide a theoretical basis for the optimization of the low-cost clean steel platform technology.

Mn13 high manganese wear-resistant steel exhibits excellent wear resistance under strong impact wear conditions. Mn13 steel mold casting products have been widely used in China for a long time, and Mn13 steel produced by continuous casting-hot rolling process has higher strength and toughness, longer service life than mold castings. However, the smelting and continuous casting production is extremely difficult. Based on the analysis of the chemical composition, properties and solidification characteristics of Mn13 steel, a new smelting and continuous casting process of Mn13 was developed based on the equipment conditions of a steel plant. Under the new process, silicon and phosphorus in molten iron could be removed through converters, and the mass fraction of phosphorus in the molten steel could be controlled below 0.010%.By adding high carbon ferromanganese and electrolytic manganese in stages in AOD furnace, the yield of alloy was significantly improved while achieving high carbon tapping. By fine-tuning the composition and compensating for temperature through LF, there was no need for vacuum treatment after LF treatment, which had the advantage of low smelting cost. The new process achieved stable continuous casting of Mn13 steel by reducing the superheat of molten steel, determining a reasonable cooling system and casting speed, using weak electromagnetic stirring and soft reduction at the end of solidification.