Foaming slag (FS) practice, typically made by fossil carbon, is a fundamental process in electric arc furnace (EAF) steelmaking, essential for enhancing arc thermal efficiency, protecting refractory linings, and optimizing melt quality. Utilizing biomass-derived carbonaceous materials to achieve comparable foaming performance offers a viable pathway for significantly reducing carbon emissions. Although coconut shell carbon and rubber can be used as biomass foaming materials, their density is low and cannot achieve a stable and lasting effect of FS. In this study, block of coconut-shell charcoal (BCSC), block of rubber particles (BRP), blends of coconut shell charcoal (CSC) and rubber particles (BCR), and blends of biomass material and ferric oxide (BFB) were prepared from CSC, rubber powder, and ferric oxide powder. Their potential as foaming agents (FA) was investigated by a hot test simulation of a tube furnace. The experiment overcame the disadvantage that biomass materials with low density could not be deposited in the slag, and it was found that the synergistic foaming of composite materials had more advantages than single-material foaming. According to the foaming time (FT), foaming height (FH), and comprehensive foaming index (CFI), the FA was sorted from high to low according to their efficiency: BFB > BCSC > BCR > BRP. Based on the experimental results, the different foaming reaction mechanisms of the four types of materials were discussed. The optimized BFB4 exhibited superior performance, achieving a 1522 s FT, a 60% increase in relative FH, and a 7914 mm·s CFI, representing the most effective foaming behavior among the tested samples. Thus, BFB4 is expected to be a promising foaming material for EAF production. Preliminary evaluation shows that it does not have side effects on the dust removal system of molten steel, slag, and flue gas and has the potential to replace fossil carbon.
The influence of MgO content on ultra-high basicity mould powders for high-speed thin slab continuous casting was examined. Powders containing 1–7 wt% MgO were prepared, and their melting behaviour, viscosity, transition temperature, and crystallisation characteristics were evaluated. Raman analysis confirms that MgO acts as a network modifier, lowering the degree of silicate polymerisation (Q 2 →Q 1 ). The XRD results demonstrate that MgO participates in the crystallisation process. As the MgO content increases, the melting temperature of the mold powder decreases slightly at first and then rises, becoming significantly higher when MgO exceeds 5 wt%. The high-temperature viscosity remains around 0.2 Pa·s, while the transition temperature decreases, resulting in an extended liquid-phase region. The crystallisation onset temperature shifts to lower values, and the crystallisation time is shortened, indicating faster crystallisation. Twin-wire measurements show that Increasing MgO content from 1 to 3 wt% decreases the solidification fraction from 91.98% to 88.17%, while further increasing MgO to 5 and 7 wt% results in only slight fluctuations, with F s values of 89.52% and 89.74%, respectively. and increase the thickness of the liquid slag film, thus enhancing lubrication. At the same time, the crystallised fraction increases, improving thermal insulation. For the investigated mold-flux composition and experimental conditions, 3–5 wt% MgO provides a relatively balanced combination of liquid slag fraction, crystallized fraction, melting behavior and thermal regulation.
With the rapid development of modern industry, the performance requirements for wear-resistant materials continue to escalate, and traditional bainitic wear-resistant steel faces performance bottlenecks and cost constraints. Silicon-Manganese bainitic wear-resistant cast steel can obtain carbide-free bainitic microstructures with an excellent combination of strength, toughness and wear resistance through the addition of low-cost alloying elements combined with simple heat treatment processes, meeting the demands of complex working conditions. It has been widely applied in numerous fields including mining machinery, rail transit and automobile. This paper reviews the research progress of bainitic wear-resistant cast steel with silicon and manganese as the main alloying elements, summarizes the effects of alloy composition design and multi-element microalloying on its microstructure and properties, and discusses the optimization mechanisms of different casting and heat treatment processes. Finally, the future development directions of new types of bainitic wear-resistant steel are prospected and summarized.
Al 2 O 3 –SiC–C (ASC) castables are increasingly used for the construction and repair of blast-furnace hearths and iron runners, where their service reliability is limited by cyclic thermal loading and its interaction with oxidation, slag/iron penetration, and structural constraint. This review critically examines the thermal-shock damage of ASC castables from four connected perspectives: service conditions, experimental characterization, theoretical and multiscale modeling, and composition–microstructure design. Conventional residual-strength tests are compared with integrated wedge-splitting, digital image correlation, acoustic-emission, and X-ray computed-tomography (XCT) approaches that link macroscopic fracture response to surface strain localization and three-dimensional crack evolution. Classical thermoelastic and energy-based criteria remain useful for first-order ranking, but their assumptions of homogeneity and temperature-independent properties limit their direct application to porous, multiphase ASC systems. A service-oriented predictive framework therefore requires temperature-dependent constitutive data, interfacial fracture laws, corrosion- or reaction-induced eigenstrain, and validation against in situ and three-dimensional damage measurements. Aggregate tailoring, SiC/C optimization, sol bonding, and reactive additives improve thermal-shock resistance mainly through controlled volume change, pore regulation, interfacial strengthening, crack deflection and bridging, and oxidation protection. Future work should establish standardized thermo-chemo-mechanical test protocols and quantitative composition–microstructure–damage–lifetime relationships for blast-furnace lining design.
During continuous casting (CC), the ladle outlet temperature gradually decreases within each heat and changes abruptly during ladle exchange, causing transient heat loss and temperature fluctuations in the tundish. These fluctuations make it difficult to achieve low-superheat and constant-temperature pouring. Although induction heating (IH) provides efficient active thermal compensation, most previous studies assumed steady inlet temperature or constant IH power, limiting their applicability to actual CC. In this study, a transient numerical model was developed for a six-strand tundish to evaluate a dynamic IH strategy that accounts for ladle outlet temperature drop and multi-ladle teeming. Four cases were simulated: no IH, constant IH powers of 400 and 800 kW, and dynamic IH with power linearly adjusted according to the average outlet temperature. The results show that dynamic IH maintains the outlet temperature within 1800 ± 2 K, reduces the standard deviations of outlet temperature and maximum temperature difference to 0.19 and 0.03 K, respectively, and achieves inclusion removal rates of 71.93% at the free surface and 21.65% within the channel. This strategy effectively compensates for transient heat loss, improves temperature uniformity, and enhances inclusion removal, providing a feasible approach for stable and high-quality CC.
