【作者】 林勤； 郭锋； 朱兴元；

【Author】 Lin Qin , Guo Feng, Zhu Xingyuan (Department of Physical Chemistry, University of Science and Technology Beijing, Beijing 100083, China;Inner Mongolia University of Technology, Huhhot 010062, China; Wuhan University of Technology, Wuhan 430070, China)

【机构】 北京科技大学物理化学系； 内蒙古工业大学材料科学与工程学院； 武汉理工大学材料科学与工程学院；

【摘要】 本文应用高分辨TEM,SEM和XRD研究碳锰洁净钢中镧和铈的存在形式,分布和在晶界的行为。研究结果表明,镧和铈在洁净钢中存在有固溶态,稀土夹杂物和稀土第二相。固溶稀土偏析在晶界,洁净钢中稀土仍有净化钢液和变质夹杂的作用。适量稀土能减少S 和P在晶界的偏析,净化晶界提高钢的冲击韧性。过量稀土在晶界产生有害的稀土第二相,□导致性能显著降低。更多还原

【Abstract】 In carbon manganese cleanliness steel the behaviors of La and Ce on grain boundaries were investigated by high-resolution transmission electron microscope (HRTEM), SEM, EDS and XRD analysis. The existent phases of RE have solid solution La or Ce, RE inclusion and RE second phase (RE-Fe-P, Fe-La, Fe-La eutectic and Fe-Ce phase) in cleanliness steel. The dissolved La or Ce segregates in the grain boundaries. That reduces the segregation of both S and P on grain boundaries at suitable RE content. It improves the strength of grain boundaries and enhances the impact toughness of steel obviously. La and Ce still have actions of purifying the molten steel and transmogrifying inclusion in cleanliness steel. While the excess La or Ce, La-Fe-P, La-P and Fe-La eutectic or Ce-Fe-P and Fe-Ce intermetallic compound can form along grain boundaries. It leads to decreasing the impact energy of steel significantly.更多还原