稀土钇处理对铁路辙叉用高锰钢中夹杂物的改性  

Modification of inclusions in high manganese steel for railway frog treated with rare earth Y

作　　者：李荣 孟倩 李涛 谭敏 陈晨[2] 张福成 LI Rong;MENG Qian;LI Tao;TAN Min;CHEN Chen;ZHANG Fucheng(College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,Hebei,China;State Key Laboratory of Metastable Materials Science and Technology,Yanshan University,Qinhuangdao 066004,Hebei,China)

机构地区：[1]华北理工大学冶金与能源学院,河北唐山063210 [2]燕山大学亚稳材料制备与科学国家重点实验室,河北秦皇岛066040

出　　处：《中国冶金》2023年第12期66-78,共13页China Metallurgy

基　　金：国家自然科学基金面上项目(52074056);河北省自然科学基金项目(E2020318006);唐山市科技创新团队培养计划项目(21130209D)。

摘　　要：高锰钢辙叉是铁路运输系统的关键部件,对铁路安全运行具有重要影响。钢中夹杂物严重影响钢的性能,稀土改性夹杂物是控制夹杂物的有效手段。基于热力学和第一性原理计算以及试验研究,系统分析了铁路辙叉用高锰钢稀土处理前后夹杂物的演变及其对钢性能的影响。热力学计算结果表明,未添加稀土Y时,高锰钢中主要的夹杂物为MnS和Al_(2)O_(3);添加稀土Y后,高锰钢中的MnS和Al_(2)O_(3)转变为Y_(2)S_(3)、YS、YAlO_(3)、Y_(2)O_(3)和Y_(2)O_(2)S;当Y质量分数为0.03%时,夹杂物全部转变为稀土夹杂物。第一性原理计算结果表明,高锰钢中夹杂物形成并稳定存在的顺序为Y_(2)O_(3)>YAlO_(3)>Y_(2)O_(2)S>Al_(2)O_(3)>Y_(2)S_(3)>YS>MnS。Al_(2)O_(3)、YAlO_(3)对高锰钢的性能不利,而含稀土夹杂物具有相对较好的延展性和弹性,可有效降低夹杂物周围的应力集中。钢中Y添加量为0.0319%时,对高锰钢中夹杂物的改性效果最好,可生成尺寸较小的稀土夹杂物,部分复相夹杂物转变为近球形的Y_(2)S_(3)-Y_(2)O_(2)S,外层Y_(2)S_(3)夹杂物弹性较好、硬度较低,可以减少夹杂物与基体的应力集中,从而有效提升高锰钢的力学性能。研究工作为稀土对钢中夹杂物的调控提供了理论依据。The high manganese steel frog is a key part of railway transportation system and has important influence on railway safety operation.Inclusion in steel has an important effect on steel properties,and rare earth modified inclusion is effective means to control inclusion.Based on thermodynamic and first principle calculation,as well as experimental research,the evolution of inclusions and their effects on the properties of high manganese steel used for railway frog before and after rare earth treatment were analyzed systematically.The thermodynamic results show that the main inclusions in high manganese steel are MnS and Al_(2)O_(3)when rare earth Y is not added.After the addition of rare earth Y,MnS and Al_(2)O_(3)in high manganese steel are transformed into Y_(2)S_(3),YS,YAlO_(3),Y_(2)O_(3)and Y_(2)O_(2)S.When Y mass fraction is 0.03%,all inclusions are transformed into rare earth inclusions.The first principle calculation results show that the order of inclusion formation and stable existence in high manganese steel is as follows,Y_(2)O_(3)>YAlO_(3)>Y_(2)O_(2)S>Al_(2)O_(3)>Y_(2)S_(3)>YS>MnS.Al_(2)O_(3)and YAlO_(3)are unfavorable to the properties of high manganese steel,while the inclusion containing rare earth has relatively good ductility and elasticity,which can effectively reduce the stress concentration around the inclusion.When the additive amount of Y in steel is 0.0319%,the modification effect of inclusions in high manganese steel is the best,and rare earth inclusions with small size are generated,some complex inclusions are transformed into near spherical Y_(2)S_(3)-Y_(2)O_(2)S,and the outer Y_(2)S_(3)inclusions have good elasticity and low hardness,which can reduce the stress concentration between inclusions and matrix,and can effectively improve the mechanical properties of high manganese steel.The research work provides a theoretical basis for the control of rare earth on inclusions in steel.

关 键 词：高锰钢 夹杂物 稀土处理 热力学计算 第一性原理计算 

分 类 号：U214.81[交通运输工程—道路与铁道工程] TG142.1[一般工业技术—材料科学与工程]