含铈IF钢中含钛夹杂物的析出行为

Precipitation behaviors of titaniferous inclusions in cerium-containing IF steel

通过热力学计算研究了IF钢中含钛夹杂物的形成过程以及铈对钢液中Al2O3夹杂物的变质机理,并采用扫描电镜、能谱仪观察和分析了IF钢和含铈IF钢中的含钛夹杂物。热力学计算和扫描电镜观察结果表明:TiN不能在熔炼温度下形成;在IF钢液凝固的过程中TiN以异质形核的形式生成并长大,生成TiN-Al2O3夹杂物;在含铈IF钢中TiN-Al2O3夹杂物被稀土铈变质为TiN-CeAlO3夹杂物,稀土铈减小了含铈IF钢中含钛复合夹杂物的尺寸。

The formation of titaniferous inclusions and the mechanism of modifying Al2O3 inclusion of cerium in IF steel were studied by thermodynamic calculation. Scanning electron microscope （SEM） and energy dispersive spec- trometer （EDS） were used to observe and analyze the titaniferous inclusions in IF steel and cerium-containing IF steel. The results of thermodynamic analysis and observation by scanning electron microscopy show that TiN can- not form at the steelmaking temperature. During the solidification process of IF steel, TiN generates by heteroge- neous nucleation and to form TiN-Al2O3 inclusion. TiN-Al2O3 inclusion can be modified into TiN-CeAlO3 inclusion by cerium in cerium-containing IF steel. The size of titaniferous compound inclusions in cerium-containing IF steel is reduced by cerium.