CSP热轧TRIP 600钢的连续冷却相变行为
|
摘要
利用Thermecmastor-Z型热模拟试验机、Formastor-F型相变仪,结合光学显微镜、扫描电子显微镜及显微硬度计等设备系统研究了CSP热轧TRIP 600钢的连续冷却相变行为,获得了试验钢的动态及静态CCT曲线,探讨了形变和冷速对其相变行为的影响。研究结果表明:随着冷速的增加,试验钢中铁素体转变温度逐渐降低,体积分数不断减少,其转变温度范围为480~716℃;珠光体含量则先增加后减少,转变温度范围为519~647℃。当冷速大于2℃/s时,试验钢中已出现贝氏体转变,其含量随冷速的增加先增大后减小,转变温度范围为451~533℃。试验钢经变形后,钢中铁素体、珠光体及贝氏体转变温度范围往左上方移动,分别为550~760、539~708和478~550℃,而且相同冷速下钢中组织更加细小。此外,变形也会提高奥氏体的机械稳定性,抑制马氏体转变,使得马氏体开始转变温度Ms由418℃降至360℃。
The continuous cooling transformation behavior of hot rolled TRIP 600 steel produced by CSP process was investigated by means of Thermecmastor-Z thermal simulation testing machine,Formastor-F full automatic transformation instrument,OM,SEM and microhardness tester.The dynamic and static continuous cooling transformation(CCT)curves of the experimental steel were obtained.And the effect of deformation on phase transformation behavior was discussed.The results show that the temperature of austenite to ferrite and the volume fraction of ferrite gradually decrease with the increase of cooling rate.The transformation temperature range of the pro-eutectoid ferrite is 480-716℃.Meanwhile,the transformation temperature range of pearlite is 519-647℃,and the volume fraction of pearlite increases first then decreases with the increase of cooling rate.When the cooling rate is larger than 2℃/s,the bainite phase transformation will take place.The volume fraction of bainite also increases first then decreases with the increase of cooling rate.The transformation temperature range is 451-533℃.Moreover,it is found that the hot deformation of austenite will refine the microstructure and promote the ferrite,pearlite and bainite transformation,the corresponding transformation temperature ranges alter to 550-760,539-708 and 478-550℃,which move to the left top places in the dynamic CCT curve.In addition,the de-formation will also enhance the mechanical stability of austenite,leading to the inhibition of martensitic transformation and decrease the martensite starting temperature(Ms)from 418℃to 360℃.
The continuous cooling transformation behavior of hot rolled TRIP 600 steel produced by CSP process was investigated by means of Thermecmastor-Z thermal simulation testing machine,Formastor-F full automatic transformation instrument,OM,SEM and microhardness tester.The dynamic and static continuous cooling transformation(CCT)curves of the experimental steel were obtained.And the effect of deformation on phase transformation behavior was discussed.The results show that the temperature of austenite to ferrite and the volume fraction of ferrite gradually decrease with the increase of cooling rate.The transformation temperature range of the pro-eutectoid ferrite is 480-716℃.Meanwhile,the transformation temperature range of pearlite is 519-647℃,and the volume fraction of pearlite increases first then decreases with the increase of cooling rate.When the cooling rate is larger than 2℃/s,the bainite phase transformation will take place.The volume fraction of bainite also increases first then decreases with the increase of cooling rate.The transformation temperature range is 451-533℃.Moreover,it is found that the hot deformation of austenite will refine the microstructure and promote the ferrite,pearlite and bainite transformation,the corresponding transformation temperature ranges alter to 550-760,539-708 and 478-550℃,which move to the left top places in the dynamic CCT curve.In addition,the de-formation will also enhance the mechanical stability of austenite,leading to the inhibition of martensitic transformation and decrease the martensite starting temperature(Ms)from 418℃to 360℃.
引文
[1]李麟.相变塑性钢—原理、性能、设计和应用[M].北京:科学出版社,2009.(Li L.Transformation Induced Plasticity Steel-Principles,Performance,Design and Applications[M].Beijing:Science Press,2009.)
[2]刘仁东.新型高强度和超高强度相变诱发塑性钢研制[D]//沈阳:东北大学,2013.(Liu R D.Study on new type high strength and ultra high strength transformation induced plasticity steels[D]//Shenyang:Northeastern University,2013.)
[3]韦习成,李麟,符仁钰.TRIP钢显微组织与性能关系的评述[J].钢铁研究学报,2001,13(5):71.(Wei X C,Li L,Fu R Y.Review on relation between microstructures and properties of TRIP steel[J].Journal of Iron and Steel Research,2001,13(5):71)
[4]汪淼,张聪,胡锋,等.相变诱导塑性汽车用钢的发展现状与趋势[J].钢铁研究学报,2016,28(8):1.(Wang M,Zhang C,Hu F,et al.Current status and trend of TRIP automotive steels[J].Journal of Iron and Steel Research,2016,28(8):1.)
[5]Xiong Z P,Kostryzhev A G,Chen L,et al.Microstructure and mechanical properties of strip cast TRIP steel subjected to thermo-mechanical simulation[J].Materials Science and Engineering,2016,677A:356.
[6]尹云洋,杨王玥,李建成,等.基于动态相变热轧C-Mn-Si系TRIP钢的组织及性能[J].材料热处理学报,2009,30(3):84.(Yin Y Y,Yang W Y,Li J C,et al.Microstructure and mechanical properties of hot rolled C-Mn-Si TRIP steel based on dynamic transformation[J].Transactions of Materials and Heat Treatment,2009,30(3):84.)
[7]唐代明.TRIP钢中合金元素的作用和处理工艺的研究进展[J].钢铁研究学报,2008,20(1):1.(Tang D M.Review of alloying elements and processing of TRIP steels[J].Journal of Iron and Steel Research,2008,20(1):1.)
[8]侯晓英.热轧及冷轧快速退火低硅含磷TRIP钢组织性能研究[D]//沈阳:东北大学,2012.(Hou X Y.Research on microstructure and mechanical properties of hot-rolled and cold-rolled rapid annealing low silicon TRIP steel containing phosphorus[D]//Shenyang:Northeastern University,2012.)
[9]Zarei H A,Hodgson P D,Yue S.Hot deformation characteristics of Si-Mn TRIP steels with and without Nb microalloy additions[J].ISIJ International,2007,35(3):324.
[10]李壮,吴迪.热机械控制工艺对热轧TRIP钢力学性能的影响[J].钢铁,2007,42(2):39.(Li Z,Wu D.Effect of thermo mechanical controlled processing on the mechanical properties of hot rolled TRIP steel[J].Iron and Steel,2007,42(2):39.)
[11]田乃媛.薄板坯连铸连轧[M].北京:冶金工业出版社,2004.(Tian N Y.Thin Slab Casting and Rolling[M].Beijing:Metallurgical Industry Press,2004.)
[12]徐少红,刘晓.薄板坯连铸连轧生产热轧TRIP钢可行性分析[J].锻压技术,2007,32(4):79.(Xu S H,Liu X.Feasibility analysis of producing hot rolled TRIP steels using TSCR process[J].Forging and Stamping Technology,2007,32(4):79.)
[13]Xiong Z P,Kostryzhev A G,Saleh A A,et al.Microstructures and mechanical properties of TRIP steel produced by strip casting simulated in the laboratory[J].Materials Science and Engineering,2016,664A:26.
[14]徐光,王巍,张鑫强.金属材料CCT曲线测定及绘制[M].北京:化学工业出版社,2009.(Xu G,Wang W,Zhang X Q.Metal Material Determination and Graphing of CCT Curve[M].Beijing:Chemical Industry Press,2009)
[15]崔忠圻,覃耀春.金属学与热处理[M].2版.北京:机械工业出版社,2009.(Cui Z Q,Qin Y C.Metal and Heat treatment[M].2nd edition.Beijing:Mechanical Industry Press,2009.)
[16]张迎晖,康永林,于浩,等.C-Si-Mn系TRIP钢连续冷却过程相变研究[J].机械工程材料,2005,29(12):4.(Zhang Y H,Kang Y L,Yu H,et al.Transformation of C-Si-Mn TRIP steel during continuous cooling[J].Materials for Mechanical Engineering,2005,29(12):4)
[17]Wang B X,Jiang Y T,Xu X D,et al.Effect of austenite deformation on continuous cooling transformation microstructures for 22CrSH gear steel[J].Journal of Iron and Steel Research International,2007,14(1):69.
[18]Pandi R,Yue S.Dynamic transformation of austenite to ferrite in low carbon steel[J].ISIJ International,1994,34(3):270.
[19]乔桂英,肖福仁,胡怡,等.热变形对86CrMoV7钢过冷奥氏体连续冷却转变的影响[J].钢铁研究学报,2000,34(1):42.(Qiao G Y,Xiao F R,Hu Y,et al.Effect of hot deformation on continuous cooling transformation for super-cooling austenite of 86CrMoV7steel[J].Journal of Iron and Steel Research,2000,34(1):42.)
[20]Barcellona A,Palmeri D.Effect of plastic hot deformation on the hardness and continuous cooling transformations of22MnB5microalloyed boron steel[J].Metallurgical and Materials Transactions,2009,40A(5):1160.
[21]刘宗昌,王海燕,任慧平,等.贝氏体铁素体形核机理求索[J].材料热处理学报,2007,28(1):53.(Liu Z C,Wang H Y,Ren H P,et al.Investigation of bainite ferrite nucleation mechanism[J].Transactions of Materials and Heat Treatment,2007,28(1):53.)
[22]刘宗昌,计云萍,任慧平.贝氏体相变理论研究新进展[J].内蒙古科技大学学报.2012,31(1):34.(Liu Z C,Ji Y P,Ren H P.Latest advance in theoretical study on bainite phase transformation[J].Journal of Inner Mongolia University of Science and Technology,2012,31(1):34.)
[23]刘宗昌,任慧平.贝氏体与贝氏体相变[M].北京:冶金工业出版社,2009.(Liu Z C,Ren H P.Bainite and Bainite Phase Transformation[M].Beijing:Metallurgical Industry Press,2009.)
[24]田村今男.奥氏体热变形行为和形变热处理(三)[J].钢铁,1985,20(3):63.(Tian C J N.Hot deformation behavior and thermo-mechanical treatment of austenite(3)[J].Iron and Steel,1985,20(3):63.)
[25]Nikravesh M,Naderi M,Akbari G H.Influence of hot plastic deformation and cooling rate on martensite and bainite start temperatures in 22MnB5steel[J].Materials Science and Engineering,2012,540A(4):24.
[26]Naderi M,Saeed-Akbari A,Bleck W.The effects of non-isothermal deformation on martensitic transformation in22MnB5steel[J].Materials Science and Engineering,2008,487A(1/2):445.
[2]刘仁东.新型高强度和超高强度相变诱发塑性钢研制[D]//沈阳:东北大学,2013.(Liu R D.Study on new type high strength and ultra high strength transformation induced plasticity steels[D]//Shenyang:Northeastern University,2013.)
[3]韦习成,李麟,符仁钰.TRIP钢显微组织与性能关系的评述[J].钢铁研究学报,2001,13(5):71.(Wei X C,Li L,Fu R Y.Review on relation between microstructures and properties of TRIP steel[J].Journal of Iron and Steel Research,2001,13(5):71)
[4]汪淼,张聪,胡锋,等.相变诱导塑性汽车用钢的发展现状与趋势[J].钢铁研究学报,2016,28(8):1.(Wang M,Zhang C,Hu F,et al.Current status and trend of TRIP automotive steels[J].Journal of Iron and Steel Research,2016,28(8):1.)
[5]Xiong Z P,Kostryzhev A G,Chen L,et al.Microstructure and mechanical properties of strip cast TRIP steel subjected to thermo-mechanical simulation[J].Materials Science and Engineering,2016,677A:356.
[6]尹云洋,杨王玥,李建成,等.基于动态相变热轧C-Mn-Si系TRIP钢的组织及性能[J].材料热处理学报,2009,30(3):84.(Yin Y Y,Yang W Y,Li J C,et al.Microstructure and mechanical properties of hot rolled C-Mn-Si TRIP steel based on dynamic transformation[J].Transactions of Materials and Heat Treatment,2009,30(3):84.)
[7]唐代明.TRIP钢中合金元素的作用和处理工艺的研究进展[J].钢铁研究学报,2008,20(1):1.(Tang D M.Review of alloying elements and processing of TRIP steels[J].Journal of Iron and Steel Research,2008,20(1):1.)
[8]侯晓英.热轧及冷轧快速退火低硅含磷TRIP钢组织性能研究[D]//沈阳:东北大学,2012.(Hou X Y.Research on microstructure and mechanical properties of hot-rolled and cold-rolled rapid annealing low silicon TRIP steel containing phosphorus[D]//Shenyang:Northeastern University,2012.)
[9]Zarei H A,Hodgson P D,Yue S.Hot deformation characteristics of Si-Mn TRIP steels with and without Nb microalloy additions[J].ISIJ International,2007,35(3):324.
[10]李壮,吴迪.热机械控制工艺对热轧TRIP钢力学性能的影响[J].钢铁,2007,42(2):39.(Li Z,Wu D.Effect of thermo mechanical controlled processing on the mechanical properties of hot rolled TRIP steel[J].Iron and Steel,2007,42(2):39.)
[11]田乃媛.薄板坯连铸连轧[M].北京:冶金工业出版社,2004.(Tian N Y.Thin Slab Casting and Rolling[M].Beijing:Metallurgical Industry Press,2004.)
[12]徐少红,刘晓.薄板坯连铸连轧生产热轧TRIP钢可行性分析[J].锻压技术,2007,32(4):79.(Xu S H,Liu X.Feasibility analysis of producing hot rolled TRIP steels using TSCR process[J].Forging and Stamping Technology,2007,32(4):79.)
[13]Xiong Z P,Kostryzhev A G,Saleh A A,et al.Microstructures and mechanical properties of TRIP steel produced by strip casting simulated in the laboratory[J].Materials Science and Engineering,2016,664A:26.
[14]徐光,王巍,张鑫强.金属材料CCT曲线测定及绘制[M].北京:化学工业出版社,2009.(Xu G,Wang W,Zhang X Q.Metal Material Determination and Graphing of CCT Curve[M].Beijing:Chemical Industry Press,2009)
[15]崔忠圻,覃耀春.金属学与热处理[M].2版.北京:机械工业出版社,2009.(Cui Z Q,Qin Y C.Metal and Heat treatment[M].2nd edition.Beijing:Mechanical Industry Press,2009.)
[16]张迎晖,康永林,于浩,等.C-Si-Mn系TRIP钢连续冷却过程相变研究[J].机械工程材料,2005,29(12):4.(Zhang Y H,Kang Y L,Yu H,et al.Transformation of C-Si-Mn TRIP steel during continuous cooling[J].Materials for Mechanical Engineering,2005,29(12):4)
[17]Wang B X,Jiang Y T,Xu X D,et al.Effect of austenite deformation on continuous cooling transformation microstructures for 22CrSH gear steel[J].Journal of Iron and Steel Research International,2007,14(1):69.
[18]Pandi R,Yue S.Dynamic transformation of austenite to ferrite in low carbon steel[J].ISIJ International,1994,34(3):270.
[19]乔桂英,肖福仁,胡怡,等.热变形对86CrMoV7钢过冷奥氏体连续冷却转变的影响[J].钢铁研究学报,2000,34(1):42.(Qiao G Y,Xiao F R,Hu Y,et al.Effect of hot deformation on continuous cooling transformation for super-cooling austenite of 86CrMoV7steel[J].Journal of Iron and Steel Research,2000,34(1):42.)
[20]Barcellona A,Palmeri D.Effect of plastic hot deformation on the hardness and continuous cooling transformations of22MnB5microalloyed boron steel[J].Metallurgical and Materials Transactions,2009,40A(5):1160.
[21]刘宗昌,王海燕,任慧平,等.贝氏体铁素体形核机理求索[J].材料热处理学报,2007,28(1):53.(Liu Z C,Wang H Y,Ren H P,et al.Investigation of bainite ferrite nucleation mechanism[J].Transactions of Materials and Heat Treatment,2007,28(1):53.)
[22]刘宗昌,计云萍,任慧平.贝氏体相变理论研究新进展[J].内蒙古科技大学学报.2012,31(1):34.(Liu Z C,Ji Y P,Ren H P.Latest advance in theoretical study on bainite phase transformation[J].Journal of Inner Mongolia University of Science and Technology,2012,31(1):34.)
[23]刘宗昌,任慧平.贝氏体与贝氏体相变[M].北京:冶金工业出版社,2009.(Liu Z C,Ren H P.Bainite and Bainite Phase Transformation[M].Beijing:Metallurgical Industry Press,2009.)
[24]田村今男.奥氏体热变形行为和形变热处理(三)[J].钢铁,1985,20(3):63.(Tian C J N.Hot deformation behavior and thermo-mechanical treatment of austenite(3)[J].Iron and Steel,1985,20(3):63.)
[25]Nikravesh M,Naderi M,Akbari G H.Influence of hot plastic deformation and cooling rate on martensite and bainite start temperatures in 22MnB5steel[J].Materials Science and Engineering,2012,540A(4):24.
[26]Naderi M,Saeed-Akbari A,Bleck W.The effects of non-isothermal deformation on martensitic transformation in22MnB5steel[J].Materials Science and Engineering,2008,487A(1/2):445.