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Segregation of interface elements is the main factor affecting the corrosion activity of microareas around Al2O3 inclusions rather than galvanic corrosion. In this work, the effects of segregation of Cu, V, Ni, Mo, B, and P elements on the interfacial bonding strength and microareas corrosion activity around Al2O3 inclusions are analyzed in detail using 3D atomic probe and first‐principles calculations. In the results, it is shown that Cu, V, Mo, B, and P elements reduce the stability of the α‐Fe/Al2O3 interface. In addition, the segregation of Cu, V, Mo, B, and P elements at the interface also enhances the adsorption capacity of Cl and ultimately improves the microarea corrosion activity around Al2O3 inclusions. Ni element can enhance the stability of α‐Fe/Al2O3 interface, and the segregation of Ni element at the interface weakens the adsorption capacity of Cl and ultimately reduces the microarea corrosion activity around Al2O3 inclusions. [ABSTRACT FROM AUTHOR]

Titanium‐bearing (Ti‐bearing) microalloyed steels have high strength and toughness by grain refinement effect of carbonitride precipitates. However, they can induce surface cracks of continuous casting slab when the Ti alloyed content is high. A microalloyed steel with Ti content (0.10–0.15 wt%) is carried out by thermalmechanical simulator over 600–1350 °C to analyze hot ductility evolution mechanism. Fracture surface morphology, phase transition, and behavior of precipitates of the tensile samples are investigated by experimental detection and thermodynamic calculation. The ductility–temperature curves show that the third brittle temperature range is 600–890 °C, which is mainly attributed to the thin proeutectoid ferrite film and precipitated titanium carbonitride particles, widening the embrittlement temperature ranges through of steel. In addition, the tensile samples at 890–1350 °C have good hot ductility, indicating the dynamic recrystallization of deformed austenite can trigger grain boundaries migration away from cracks and avoid the side effect of the Ti (C,N) particles on hot ductility. The first brittle temperature range of 1350 °C‐melting point is mainly ascribed to the partial melting of the grain boundaries with element segregation of sulfur and phosphorus, and microporosity loose among dendrites. [ABSTRACT FROM AUTHOR]

In the present study, the experiments for the phosphorus equilibrium partition between CaO-SiO2-Fe tO-P2O5 slags with Na2O or K2O addition and solid pure iron foil were performed at 1573, 1623, and 1673 K, respectively. The experimental results showed that both Na2O and K2O addition can enhance the dephosphorization ability of CaO-SiO2-Fe tO-P2O5 based slags and they have similar dephosphorization ability under the same temperature and main slag composition. The phosphorous partition ratio between slag and carbon-saturated hot metal increased with the increase of basicity with a peak value in the range of R around 1.3-1.5. The phosphorous partition ratio decreased with the increasing of ( w(CaO) + w(Na2O))/ w(Fe tO) value in slags. The dephosphorization ability of CaO-SiO2-Fe tO-P2O5 based slags was relatively higher when the ( w(CaO) + w(Na2O))/ w(Fe tO) values fell in the range of 0.5-0.8. The phosphorous partition ratio decreased with the temperature increase. The linear relationships between the logarithm phosphorous partition ratio and the reciprocal of temperature were obtained for CaO-SiO2-Fe tO-P2O5 based slags with Na2O. The information provides by present study would be useful for optimization of dephosphorization in hot metal pretreatment. [ABSTRACT FROM AUTHOR]