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第12期 李龙飞等：低碳含铌钢粗晶奥氏体再结晶的数值模拟 .1541. chanical control process)工艺中的奥氏体未再结晶区 Mater,1991,39:529 轧制即在此温度范围内进行.在T~T的温度范 [5]Dutta B.Palmiere E J,Sellars C M.Modelling the kinetics of strain induced precipitation in Nb microalloyed steels.Acta 围内，虽然再结晶比析出早，但由于析出的强烈阻碍 Mater,2001,49:785 作用，再结晶不能充分进行，即此温度范围内为部分 [6]Zurob HS.Hutchinson C R,Brechet Y,et al.Rationalization of 再结晶区，变形组织容易出现混晶，在制定热连轧工 the softening and recrystallization behaviour of microalloyed 艺时应避免在TR~T的温度区间内进行变形 austenite using mechanism maps.Mater Sci Eng A.2004.38; 由于涉及的温度范围较宽，对于某一特定钢种， 64 [7]Zurob HS,Hutchinson C R.Brechet Y,et al.Modeling recrys 需要进行大量的变形实验才能绘制比较准确的 tallization of microalloyed austenite:effect of coupling recovery. PTT图，而一旦合金成分改变时则需要进行重复 precipitation and reerystallization.Acta Mater,2002.50:3075 实验，从图3的结果可以看出，利用基于位错一析 [8]Wang X T.SiweckiT.Engberg G A.Physical model for predic- 出一再结晶之间交互作用模型的数值模型来绘制 tion of microst ructure evolution during thermo mechanical process- RPTT图可以显著减少实验工作量，而且适应性强， ing.Mater Sci Forum,2003,426-432:3801 仅需少量调整就可以绘制不同钢种的RPTT图. [9]Zhang L.Microstructure Control and Process Optimization of Thin Slab Direct Rolling [Dissertation].Beijing:University of 3结论 Science and Technology Beijing.2007 (张玲.TSDR工艺热加工过程的组织演变与控制[学位论 以物理治金原理为基础建立了低碳含铌钢热变 文]北京：北京科技大学，2007) 形道次间隔期间内的组织预测模型，模型以位错密 [10]Xue C X.Zhang L.Yang W Y,et al.Static reerystallization in 度作为联系析出、回复与再结晶行为之间的桥梁，综 low-carbon niobium microalloyed steels with coarse austenite. Uni Sci Technol Beijing.2008.30(4):374 合考虑析出回复一再结晶之间的交互作用.利用该 (薛春霞，张玲，杨王玥，等，低碳含铌钢粗大奥氏体的静态 模型对低碳含铌钢道次间隔期间内粗晶奥氏体的组 再结晶.北京科技大学学报，2008,30(4)：374) 织演变进行了数值模拟，结果与实验数据符合得较 [11]Deschamps A.Brechet Y.Influence of predeformation and age- 好.所得低碳含铌钢的再结晶、析出过程的再结晶 ing of an AlZn-Mg Alloy-lI Modeling of precipitation kinetics 析出一温度时间(RPTT)图对制定含铌微合金钢薄 and yield stress.Acta Mater,1998.47:293 板坯连铸连轧工艺具有很好的指导意义， [12]Liu W J.A new theory and kinetic modeling of strain induced precipitation of Nb(CN)in microalloyed austenite.Metall 参考文献 Mater Trans A.1995,26,1641 [13]DeArdo A J.Thermomechanical processing of microalloyed [1]Sellars C M.Whiteman JA.Recrystallization and grain growth in steels:grain refinement revisited//Palmiere E J.Mahfouf M, hot rolling.Met Sci.1978.13:187 Pinna C.International Conference on Thermomechanical Pro [2]Mecking H.Kocks U F.Kinetics of flow and strain-hardening. cessing:Mechanics,Microstructure.Control.Sheffield: Acta Metall,1981.29:1865 University of Sheffield.20029 [3]Yoshie A,Fujita T.Fujioka M,et al.Formulation of flow stress [14]Cahn J W.The impurity-drag effect in grain boundary motion. of Nb added steels by considering work-hardening and dynamic re- Acta Mater,1962.10:789 covery.ISIJ Int,1996,36.467 [15]Li G.Maccagno T M.Bai D Q.Effect of initial grain size on [4]Kwon 0,Deardo A J.Interactions between recrystallization and the static recrystallization kinetics of Nb microalloyed steels. precipitation in hot-deformed microalloyed steels.Acta Metall IS1J1nt,1996,36:1479chanical control process）工艺中的奥氏体未再结晶区 轧制即在此温度范围内进行．在 T R～ T′的温度范 围内虽然再结晶比析出早但由于析出的强烈阻碍 作用再结晶不能充分进行即此温度范围内为部分 再结晶区变形组织容易出现混晶在制定热连轧工 艺时应避免在 T R～ T′的温度区间内进行变形． 由于涉及的温度范围较宽对于某一特定钢种 需要进行大量的变形实验才能绘制比较准确的 RPTT 图而一旦合金成分改变时则需要进行重复 实验．从图3的结果可以看出利用基于位错－析 出－再结晶之间交互作用模型的数值模型来绘制 RPTT 图可以显著减少实验工作量而且适应性强 仅需少量调整就可以绘制不同钢种的 RPTT 图． 3 结论 以物理冶金原理为基础建立了低碳含铌钢热变 形道次间隔期间内的组织预测模型．模型以位错密 度作为联系析出、回复与再结晶行为之间的桥梁综 合考虑析出－回复－再结晶之间的交互作用．利用该 模型对低碳含铌钢道次间隔期间内粗晶奥氏体的组 织演变进行了数值模拟结果与实验数据符合得较 好．所得低碳含铌钢的再结晶、析出过程的再结晶－ 析出－温度－时间（RPTT）图对制定含铌微合金钢薄 板坯连铸连轧工艺具有很好的指导意义． 参 考 文 献 ［1］ Sellars C MWhiteman J A．Recrystallization and grain growth in hot rolling．Met Sci197813：187 ［2］ Mecking HKocks U F．Kinetics of flow and strain-hardening． Acta Metall198129：1865 ［3］ Yoshie AFujita TFujioka Met al．Formulation of flow stress of Nb added steels by considering work-hardening and dynamic recovery．ISIJ Int199636：467 ［4］ Kwon ODeardo A J．Interactions between recrystallization and precipitation in hot-deformed microalloyed steels． Acta Metall Mater199139：529 ［5］ Dutta BPalmiere E JSellars C M．Modelling the kinetics of strain induced precipitation in Nb microalloyed steels． Acta Mater200149：785 ［6］ Zurob H SHutchinson C RBrechet Yet al．Rationalization of the softening and recrystallization behaviour of microalloyed austenite using mechanism maps．Mater Sci Eng A200438： 64 ［7］ Zurob H SHutchinson C RBrechet Yet al．Modeling recrystallization of microalloyed austenite：effect of coupling recovery precipitation and recrystallization．Acta Mater200250：3075 ［8］ Wang X TSiwecki TEngberg G A．Physical model for prediction of microstructure evolution during thermo mechanical processing．Mater Sci Forum2003426－432：3801 ［9］ Zhang L． Microstructure Control and Process Optimiz ation of Thin Slab Direct Rolling ［Dissertation ］．Beijing：University of Science and Technology Beijing2007 （张玲．TSDR 工艺热加工过程的组织演变与控制 ［ 学位论 文］．北京：北京科技大学2007） ［10］ Xue C XZhang LYang W Yet al．Static recrystallization in low-carbon niobium-microalloyed steels with coarse austenite．J Uni Sci Technol Beijing200830（4）：374 （薛春霞张玲杨王 等．低碳含铌钢粗大奥氏体的静态 再结晶．北京科技大学学报200830（4）：374） ［11］ Deschamps ABrechet Y．Influence of predeformation and ageing of an A-l Zn-Mg Alloy-Ⅱ Modeling of precipitation kinetics and yield stress．Acta Mater199847：293 ［12］ Liu W J．A new theory and kinetic modeling of strain-induced precipitation of Nb （CN ） in microalloyed austenite． Metall Mater T rans A199526：1641 ［13］ DeArdo A J． Thermomechanical processing of microalloyed steels：grain refinement revisited∥Palmiere E JMahfouf M Pinna C．International Conference on Thermomechanical Processing： Mechanics Microstructure ＆ Control．Sheffield： University of Sheffield2002：9 ［14］ Cahn J W．The impurity-drag effect in grain boundary motion． Acta Mater196210：789 ［15］ Li GMaccagno T MBai D Q．Effect of initial grain size on the static recrystallization kinetics of Nb microalloyed steels． ISIJ Int199636：1479 第12期 李龙飞等： 低碳含铌钢粗晶奥氏体再结晶的数值模拟 ·1541·