Behaviors of Lanthanum and Cerium on Grain Boundaries in Carbon Manganese Clean Steel  

作　　者：林勤 郭锋 朱兴元 

机构地区：[1]Department of Physical Chemistry, University of Science and Technology Beijing [2]Inner Mongolia University of Technology [3]Wuhan University of Technology

出　　处：《Journal of Rare Earths》2007年第4期485-489,共5页稀土学报（英文版）

基　　金：Project supported by the Ministry of Science and Technology of China (2002BA315A-5)

摘　　要：The behaviors of La and Ce on gram boundaries in carbon manganese clean steel were investigated by high-reso- lution transmission elecetron microscope （HRTEM）, scanning elecetron microscopy（SEM ）, energy dispersive spectrometer （EDS） and X-ray diffraction（XRD） analysis. The existing forms of rare earths （RE） in clean steel were as follows： dissolved in sohd solution, forming inclusion or second phase containing RE （RE-Fe-P, La-P, Fe-La eutectic and Fe-Ce phase）. The dissolved La or Ce segregated at grain boundaries. The segregation of both S and P at gram boundaries was reduced with suitable RE content. The impact toughness of the steel was improved obviously. La and Ce had effecets on purifying molten steel and modifying inclusions in clean steel, whereas with excessive La or Ce, La-Fe-P, La-P and Fe-La eutecetic phase or Ce-Fe-P and Fe-Ce intermetallic compound would form along grain boundaries, causing the impact energy to decrease significantly.The behaviors of La and Ce on gram boundaries in carbon manganese clean steel were investigated by high-reso- lution transmission elecetron microscope （HRTEM）, scanning elecetron microscopy（SEM ）, energy dispersive spectrometer （EDS） and X-ray diffraction（XRD） analysis. The existing forms of rare earths （RE） in clean steel were as follows： dissolved in sohd solution, forming inclusion or second phase containing RE （RE-Fe-P, La-P, Fe-La eutectic and Fe-Ce phase）. The dissolved La or Ce segregated at grain boundaries. The segregation of both S and P at gram boundaries was reduced with suitable RE content. The impact toughness of the steel was improved obviously. La and Ce had effecets on purifying molten steel and modifying inclusions in clean steel, whereas with excessive La or Ce, La-Fe-P, La-P and Fe-La eutecetic phase or Ce-Fe-P and Fe-Ce intermetallic compound would form along grain boundaries, causing the impact energy to decrease significantly.

关 键 词：LANTHANUM CERIUM grain boundaries carbon manganese clean steel rare earths 

分 类 号：TG115.2[金属学及工艺—物理冶金]