Wang Shisong,Dai Mingjie,Chen Shoujie,et al.Absorption Behavior of TiN by Different Mold Slags of High Titanium Steel[J].Special Steel,2026,47(02):57-63.
Wang Shisong,Dai Mingjie,Chen Shoujie,et al.Absorption Behavior of TiN by Different Mold Slags of High Titanium Steel[J].Special Steel,2026,47(02):57-63. DOI: 10.20057/j.1003-8620.2025-00061.
Absorption Behavior of TiN by Different Mold Slags of High Titanium Steel
To address fish-like substances caused by TiN inclusions during high-Ti steel continuous casting process, five potential mold slags for high titanium steel were designed. The TiN absorption behaviors and mechanisms by various mold slags were investigated through integrated in-situ observation, rotating cylinder tests, and thermodynamic calculations. In-situ observations revealed that the above five types of mold slags would react with TiN to produce bubbles , with CaO-SiO
2
-Al
2
O
3
(CSA)-based slag showing the strongest reactivity, followed by CaO-SiO
2
-Al
2
O
3
-BaO (CSAB)-based slag. Rotating cylinder tests demonstrated slowed TiN absorption rates of each mold slag was slow , where CSA mold slag achieved the fastest rate of 3.00×10
-3
mm/min at 1 520 ℃, followed by CSAB mold slag (2.46×10
-3
mm/min). This was consistent with the rules of in situ observation. Electron microscope observation, thermodynamic calculation and composition change before and after absorption of the reaction interface showed that the absorption rate of TiN by the protective slag was negatively correlated with the thickness of the boundary layer of the reaction.TiN primarily reacted with Na
2
O oxidizer in slags, with CSA slag exhibiting the highest Na
2
O activity and optimal absorption capacity. Its absorption mechanism is as follows: TiN reacts with the oxidi
zing components in the slag to generate TiO
2
, and TiO
2
enters the mold slag through diffusion dissolution. Therefore, the activity of the oxidizing components in the mold slag can be increased to absorb and remove TiN after oxidation.
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