一、稀土元素对钢性能的影响二、稀土在钢中的基本作用2.1稀土的净化作用及对夹杂物形态的影响(1)稀土的脱氧作用(2)稀土金属的脱硫作用及对硫化物形态的控制作用(3)稀土的其他净化作用及对其他夹杂物形态的影响2.2稀土的合金化作用及其与间隙原子的交互作用三、稀土的加入方法四、关于稀土钢浇注结瘤问题 First, the rare earth elements on the steel properties Second, the basic role of rare earth in steel 2.1 Purification of rare earth and inclusions Morphology (1) the role of rare earth deoxidation (2) rare earth metal desulfurization and sulfide morphology (3) other purification of rare earth and other inclusions Morphology 2.2 rare earth alloying effect and interaction with the interstitial atoms Third, the method of adding rare earth four, on the rare earth steel casting nodules