The non-reactive CaO–Al₂O₃-based mold flux system is proposed to avoid the reaction problems during the casting process of advanced high-strength steels, when conventional CaO–SiO₂-based mold flux system is applied. However, new problems such as low consumption and insufficient lubrication are introduced during the industrials of CaO–Al₂O₃-based mold fluxes, which is closely associated with its melt structure and crystallization behavior. Herein, the studies on the melt structure and crystallization property of CaO–Al₂O₃-based mold fluxes are summarized and discussed. The structural roles of Al₂O₃, B₂O₃, and SiO₂ in CaO–Al₂O₃-based mold flux system are quite complex because the structural transformation occurs in aluminate network structure, such as [AlO₄]⁵⁻ and [AlO₅]⁷⁻, and borate network structure, such as [BO₃]³⁻ and [BO₄]⁵⁻, in the system. In addition, it is suggested that the addition of basic metal oxides and fluorides will strengthen the stability of network structure, due to the charge compensation effect of Li⁺ and Ba²⁺, and the strong electrostatic attraction between Al³⁺ and F⁻. On the contrary, many Al-bearing crystal phases with high melting point precipitate in the CaO–Al₂O₃-based melt, which will improve the crystallization ability of slag and deteriorate its lubrication performance.

中文翻译：

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先进高强度钢铸造用非反应性保护渣的熔体组织和结晶行为综述

提出了非反应性CaO-Al ₂ O ₃基保护渣系统，以避免在应用传统的CaO-SiO ₂基保护渣系统时在先进高强度钢的铸造过程中的反应问题。_{然而，CaO-Al 2} O ₃基保护渣在工业化过程中出现了消耗低、润滑不足等新问题，这与其熔体结构和结晶行为密切相关。_{本文对CaO-Al 2} O ₃基保护渣熔体结构和结晶性能的研究进行了总结和讨论。Al ₂ O ₃ , B的结构作用CaO-Al ₂ O ₃基保护渣体系中的₂ O ₃和 SiO _{2相当复杂，因为结构转变发生在铝酸盐网络结构中，如 [AlO 4} ] ^5-和 [AlO ₅ ] ^7-，以及硼酸盐网络结构，如系统中的[BO ₃ ] ³⁻和[BO ₄ ] ⁵⁻。此外，由于Li ⁺和Ba ^{2+的电荷补偿作用，建议添加碱性金属氧化物和氟化物将增强网络结构的稳定性。，以及Al 3+}和F ^-之间的强静电引力。_{相反，在CaO-Al 2} O ₃基熔体中析出许多高熔点的含Al晶相，这会提高渣的结晶能力，降低其润滑性能。