摘要
利用高温共聚焦激光显微镜(CLSM)将4个炉次的高等级轴承钢样品加热至液态,炼钢温度下动态原位观察夹杂物碰撞长大行为,保温后快速冷却,再利用扫描电镜观察试样中的夹杂物,并用能谱分析EDS确定其成分。结果表明,未经过高温共聚焦显微镜处理的轴承钢原始样中夹杂物主要是尖晶石核心外包覆CaS;经过相应处理的轴承钢试样中夹杂物则主要是球状铝酸钙夹杂物,并观察到部分液态的铝酸钙夹杂物在钢液-气相界面铺展,同时观察到了铝酸钙夹杂物与镁铝尖晶石碰撞长大。根据观察结果可判断,轴承钢钢液中液态化程度高的铝酸钙夹杂物相互碰撞以及其与镁铝尖晶石之间的碰撞融合长大是形成Ds夹杂物的重要原因,降低钢中钙含量可以降低夹杂物中的CaO含量,从而提高夹杂物熔点以降低其在钢液中的液态化程度,从而减少Ds夹杂物形成。
The behaviors of inclusions in liquid bearing steel were in-situ observed with confoeal laser scanning mi- croscopy （CLSM）. Samples from 4 heats were reheated to steel making temperature, and after a period of holding the samples were rapidly cooled. Then the samples were observed under SEM with EDS to analyze inclusions. The results show that inclusions in original hearing steel samples are mostly MgO ~ AI2 03 with out-layer of CaS, while inclusions in liquid bearing steel after CLSM treatment are xA1203 ~ yCaO. The inclusions with high liquid ratio spread on the interface between liquid steel and argon gas, as well as there are collision and combination of xAl2 03 · yCaO and MgO, Al2 03. It can be concluded that the main formation cause of Ds inclusions is collision and combination between xA1203 · yCaO inclusions with high liquid ratio or between these inclusions and MgO · Al2O3 inclusions. Reducing Ca content in liquid steel to decrease CaO content in inclusions and the liquidation of inclusions can decrease the formation of Ds inclusions.
出处
《钢铁研究学报》
CAS
CSCD
北大核心
2015年第12期48-53,共6页
Journal of Iron and Steel Research
关键词
共聚焦激光显微镜
轴承钢
Ds夹杂物
原位观察
confocal laser scanning microscope
bearing steels Ds inclusions in-situ observation
