钢液中气泡和夹杂物的去除

Bubble and inclusion removal in molten steel

熔池中钢液的流动、气泡以及夹杂物的大小都影响着钢液中夹杂物的去除率.研究表明,向上流动的钢液有利于夹杂物的上浮,几乎所有的夹杂物都能在钢液上升流中上浮.向下流动的钢液对夹杂物和气泡的上浮有阻碍作用,当气泡的直径小于1mm时其在钢液中将无法上浮.在钢包精炼吹氩过程中,应使用较小的吹氩量,一方面避免产生过大的气泡而降低底吹气体的利用效率,另一方面减小熔池内的钢液流速,促进气泡和夹杂物的上浮.但吹氩量也不宜过小,必须使气泡保持一定的尺寸来保证其充分上浮.在钢包精炼过程中选择吹氩量时,应综合考虑钢液流速和气泡大小的影响.

The inclusion removal rate in molten steel is influenced by molten steel flow and the bubble/inclusion size. As the research results shown,the upward movement of molten steel is in favor of the inclusion floatation,and almost all of the inclusions can float up. Inclusion and bubble flotation is hindered by the downward molten steel flow. Bubbles whose diameters are smaller than 1 mm can not float up when the molten steel flows downward. In the ladle refining process,small gas injection rate should be used to avoid forming excessive big bubbles,which will reduce the gas-injection efficiency,and to reduce the molten steel velocities,which is good for the bubble/inclusion flotation. But the gas injection rate also should not be too small,which ensures that bubbles in molten steel maintain a certain size to fully float up. In the ladle refining process,both the molten steel velocity and the bubble size should be considered when choosing the gas injection rate.