钢铁材料中形变诱导相变超细化机理研究  

The study on the ultrafine mechanism of steels: strain-induced phase-transformation form austenite to ferrite

作　　者：张国英[1] 张辉[1] 刘春明[2] 周永军[1] 

机构地区：[1]沈阳师范大学物理科学与技术学院,沈阳110034 [2]东北大学材料冶金学院,沈阳110006

出　　处：《物理学报》2005年第4期1771-1776,共6页Acta Physica Sinica

基　　金：辽宁省教育厅科学研究计划 (批准号 :2 0 0 4C0 0 8);中国博士后科学基金 (批准号 :2 0 0 40 3 6112 );国家高技术研究发展计划 (批准号 :2 0 0 3AA3 3 1170 );沈阳师范大学材料实验中心资助的课题~~

摘　　要：通过计算机编程建立奥氏体相中 12 [110 ]刃位错、奥氏体相中非形变区和形变区奥氏体 铁素体相界模型 .用实空间的连分数方法计算了非形变区和形变区奥氏体 铁素体相界界面能 ,计算了碳、氮及微合金元素在完整晶体及位错区引起的环境敏感镶嵌能 ,进而讨论形变过程中铁素体形核的难易程度 ,碳、氮及合金元素在位错区的偏聚及析出与铁素体细化的关系 .计算结果表明 :α Fe易于在高密度位错区 (形变带、亚晶界、晶界 )形核 ,在奥氏体形变过程中 ,就会大大提高α Fe形核率 ,细化铁素体晶粒 ;碳、氮和微合金元素易于单独或共同偏聚于位错区 ,致使碳氮化物在刃位错区 (形变带、亚晶界、晶界 )区析出 ,阻碍α Fe晶粒的长大 ,使铁素体组织进一步细化 .The models of interphase boundaries of austenite/ferrite(gamma/alpha) in the undeformde austenite and deformed austenite, and the model of 1/2 [110] edge dislocation in austenite matrix were set up with computer programming. The interfacial energy of gamma/alpha interphase boundaries in the undeformde austenite and deformed austenite, the environment sensitive embedding energies (E-ESE) of C, N and microalloying elements Nb, Ti or V (in the form of air mass) in the area of edge dislocation in austenite were calculated by using recursion method. The refinement mechanism of steels in the deformation process was discussed. Interfacial energy calculation results show that the most preferred ferrite nucleation sites are the area of high density dislocations such as deformation bands, the austenite grain boundaries and subbounaries, which leads to a considerable increase in the nucleation rate. This is why ferrite grains formed in the deformed austenite are far more smaller than those in undeformed austenite. The E,S, calculation results show that C, N microalloying elements ( Nb, Ti or V) in form of the air mass C, N together with microalloying elements (Nb or Ti) in the form air mass are all easy to aggregate to the area of edge dialocations, which results in the carbonitride precipitation in there (deformation band, grain boundary or grain subboundary). The growth of ferrite grains is considerably suppressed by deformation due to impingement with carbonitride particles and other ferrite grains, which leads to the further refinement of ferrite grains.

关 键 词：钢铁材料 刃位错 晶粒细化 奥氏体 铁素体 形变诱导相变 

分 类 号：TG115[金属学及工艺—物理冶金]