Abstract: Location of medium and center crack- distance from mold meniscus ami comparison between aim temperature and surface temperature of 0. 45C steel billet 150 mm x 150 mm strand of N()2 caster and 150 nun x 220 mm straml of caster have been analyzed by maerostructure and computer simulation software for secondary cooling scheduling. Results shoeed that unsuited secondaiy cooling water rate and cooling water distributing at each part wri-e main cause to form billet crack, the occurrence ratio obviously decreased by decreasing secondary cooling water rate and optimizing cooling water distribution so that the surface temperature of strand was close to aim temperature curves and the occured ratio of billet inediuni and center crack obviously decreased.

Key words: 0. 45C Steel. Billet Casting, Center Crack, Secondary Cooling Sciieduling

摘要： 通过低倍组织和二冷制度计算机仿真软件分析了2~#连铸机150mm×150mm,4~#连铸机150mm×220 mm 45钢铸坯中心和中间裂纹发生距弯月面的位置,铸坯表面温度与目标温度的对比。结果表明,二冷比水量和各段冷却水分配不当是形成铸坯裂纹的主要原因,通过降低二冷水量和优化冷却水分配使铸坯表面温度接近目标温度曲线,明显降低了铸坯中间和中心裂纹的发生率。

关键词: 45钢, 小方坯连铸, 中心裂纹, 二冷制度