Investigation on Viscosity and Nonisothermal Crystallization Behavior of P-Bearing Steelmaking Slags with Varying TiO₂ Content

详细信息    查看全文

• 作者：Zhanjun Wang ; Yongqi Sun ; Seetharaman Sridrar…
• 刊名：Metallurgical and Materials Transactions B
• 出版年：2017
• 出版时间：February 2017
• 年：2017
• 卷：48
• 期：1
• 页码：527-537
• 全文大小：
• 刊物类别：Chemistry and Materials Science
• 刊物主题：Metallic Materials; Characterization and Evaluation of Materials; Structural Materials; Surfaces and Interfaces, Thin Films; Nanotechnology;
• 出版者：Springer US
• ISSN：1543-1916
• 卷排序：48

文摘

The viscous flow and crystallization behavior of CaO-SiO₂-MgO-Al₂O₃-Fe_tO-P₂O₅-TiO₂ steelmaking slags have been investigated over a wide range of temperatures under Ar (High purity, >99.999 pct) atmosphere, and the relationship between viscosity and structure was determined. The results indicated that the viscosity of the slags slightly decreased with increasing TiO₂ content. The constructed nonisothermal continuous cooling transformation (CCT) diagrams revealed that the addition of TiO₂ lowered the crystallization temperature. This can mainly be ascribed to that addition of TiO₂ promotes the formation of [TiO₆]-octahedra units and, consequently, the formation of MgFe₂O₄-Mg₂TiO₄ solid solution. Moreover, the decreasing viscosity has a significant effect on enhancing the diffusion of ion units, such as Ca2+ and [TiO₄]-tetrahedra, from bulk melts to the crystal–melt interface. The crystallization of CaTiO₃ and CaSiTiO₅ was consequently accelerated, which can improve the phosphorus content in P-enriched phase (n2CaO·SiO₂-3CaO·P₂O₅). Finally, the nonisothermal crystallization kinetics was characterized and the activation energy for the primary crystal growth was derived such that the activation energy increases from −265.93 to −185.41 KJ·mol−1 with the addition of TiO₂ content, suggesting that TiO₂ lowered the tendency for the slags to crystallize.