| 摘要 |
PURPOSE:To allow N2 to absorp and contain promptly into molten steel by bring the molten steel into contact with molten slag contg. CaCN2 or AlN with the stirring action caused by blowing N2 gas into molten steel. CONSTITUTION:For refining the crystal grains in steel structure, approximately 170-200ppm of N2 is allowed to contain in the steel, thereby, CaCN2 or AlN is added to the molten slag on the surface of the molten steel for allowing it contain, then stirring the molten steel by blowing N2 gas into it for bring it into contact with molten slag at wider but fresh contact surface. With the aid of CaCN2 or AlN in molten slag, N2 is, in comparatively short duration of time, absorbed to contain to an objective level of content to refine the crystal grains of the steel, resulted in improvement of steel properties. |
