【摘要】 实验钢经过真空感应炉模拟冶炼、实验测定、金相观察和理论分析,系统研究了稀土在高碳Nb钢中的赋存状态和存量的变化规律及其对钢中硫化物夹杂、微观组织及相变点的影响。研究发现,对于高碳Nb钢而言,加入大量的稀土并不能无限制的增加钢中固溶稀土含量,在现有实验条件下固溶稀土含量的最大值可以达到0.0151%。固溶稀土的存在可以改变退火态高碳Nb钢的珠光体形貌、细化热轧态的奥氏体晶粒尺寸,提高高温下奥氏体长大温度,降低Ac1、Ac3、Ar1、Ar3的相变温度和钢的线膨胀系数,提高Ms点的转变温度。更多还原

【Abstract】 Through simulation of smelting process of the test steel in vacuum induction furnace,experimental measurements,metallographic observation and theoretical analysis,existential state and change in content rules of rare earth in Nb high-carbon steel and its influence on sulfide inclusion,microstructure and phase transformation point were studied. The results show that increase of solid solubility of rare earth in Nb high-carbon steel with addition of rare earth is not an endless process. Under the present experimental conditions,the maxmum solid solubility of rare earth in the test steel can reach0. 0151%. The existence of rare earth in solid solution can change pearlite morphology of Nb high-carbon steel,refine the size of hot-rolled austenite grain,increase growth temperature in hyperthermia,reduce the phase transformation temperature of Ac1,Ac3,Ar1,Ar3and linear expansion austenite factors and improve the transition temperature of Ms.更多还原