中文摘要：

通过真空感应电炉内进行含铌铁水直接冶炼含铌微合金钢及其稀土合金化的实验,制得稀土含铌微合金钢并分析含铌钢的显微组织、力学性能及夹杂物的形态。结果表明,含铌铁水直接冶炼含铌微合金钢稀土含量下降到0.0007%,铌下降到0.018%;加入稀土合金化能够细化钢的组织,提高机械性能,改变夹杂物的形态。

英文摘要：

Nb- bearing microalloyed steel smelted directly by Nb- bearing hot metal and the steel alloyed by RE had been carried out in a vacuum induction furnace. Structures,properties and inclusion in them were analyzed. The results show that RE content in Nb- bearing steel decreases to 0. 0007% and Nb content to 0. 018%; moreover,when the Nb- bearing steel is alloyed by RE,RE can refine structures of Nb- bearing steel,improve machine properties and change shapes of inclusion in the steel.