【摘要】 通过显微组织观察和对临界转变温度的测定,研究了稀土元素La对碳锰纯净钢组织和冷却转变过程的影响。结果表明,当镧含量较高时,纯净钢冷却转变组织粗化,形成魏氏组织的趋势增加,珠光体片层间距不均匀;在碳锰纯净钢的冷却转变过程中,随La含量的增加,先共析铁素体开始析出温度降低,析出速度加快,共析转变开始温度降低。镧在晶界的偏聚是造成碳锰纯净钢组织和相变过程变化的主要原因。更多还原

【Abstract】 The effects of rare earth element La on microstructure and cooling transformation of carbon-manganese purity steels were investigated by microstructure observation and phase transformation critical temperatures determination.The results show that La leads to a tendency of grain coarsening and forming widmanstatten structure,resulting in inhomogeneous interlamellar spacing of pearlite when La content is higher.During the cooling transformation process of carbon-manganese purity steels,the precipitation starting temperature of pro-eutectoid ferrite and eutectoid decreases and the precipitation speed increases with increasing La content.The reason above varieties on carbon-manganese steels is relatiwe to La segregation in grain boundary.更多还原