包晶钢连铸保护渣固渣膜生长及成分偏析试验

 保护渣渣膜的形态及性能对提高连铸坯质量及稳定连铸生产起着至关重要的作用。采用改进型水冷铜探头冷凝获取不同探头浸入时间下的包晶钢保护渣固渣膜，通过光学显微镜及SEM观察方法检测及评价保护渣渣膜的内部结构特性，并结合SEM-EDX检测了渣膜不同部位各主要成分的偏析情况，分析了渣膜凝固过程中凝固前沿元素的偏聚规律。研究结果表明，本渣系及试验条件下，保护渣渣膜主要晶体为枪晶石与三斜霞石；枪晶石凝固析晶过程中凝固前沿成分变化促进了三斜霞石等高熔点相在渣膜凝固前沿与枪晶石混合析出，使得固渣膜厚度迅速增加。

Experiment on solidification and composition segregation of solidified mold flux film for peritectic steel continuous casting

The structure and property of mold flux films are critical factors for enhancing the quality of casting products and maintaining a stable running of casting. An improved water-cooled copper probe was adopted to obtain solid slag films with different probe immersion times. Optical microscopes and SEM were used to inspect the internal structure of films,SEM-EDX was adopted to measure the composition segregation within the film for deducing the composition change of liquid slag at solidification front. The result reveals that the major crystal forms in solid films are cuspidine and carnegieite,the precipitation of cuspidine changes the composition of liquid slag at the solidification front and pro-motes the precipitation of carnegieite,which leads to the rapid growing of solid slag film.