Abstract：For the experimental steel the middle temperature phase transition point features of the high temperature relaxation?process of the experimental steel, the isothermal phase composition under the 450 ℃, the state of microstructure, and the hardness when the isothermal time changes were studied. In order to get the new knowledge of the effect of high temperature relaxation?process to the ultra low carbon steel without Nb, Ti alloy compounds precipitate elements’ bainite transition. The results show that high temperature relaxation?process significantly affected the experimental steel’s medium temperature transformation point. Although the CCT curve had two section characteristic, it moved to the left above compared with the samples which did not go through high temperature relaxation?process. The dislocation cell structure forming in the high temperature relaxation?process led to the forming of lath bunchy bainite with smaller size under 450 ℃ short-term isothermal, and the steel have a higher level of hardness. With the extension of isothermal time, the bainite grew up, and the hardness declined. While the samples without high temperature relaxation?process went through deformation-recovery process and bainite transformation process under the same 450 ℃. These two processes both had an effect on the steel’s hardness by working together to make the hardness change slowly when the isothermal time was less than 30 min.
收稿日期: 2013-12-16
出版日期: 2014-08-05
引用本文:
刘庆锁， 杨巍巍， 袁连杰， 高 斌， 孟 亮. 高温弛豫对无Nb和Ti等元素超低碳贝氏体钢的影响[J]. 钢铁, 2014, 49(8): 88-93.
LIU Qing-suo, YANG Wei-wei, YUAN Lian-jie, GAO Bin, MENG Liang. Effect of High Temperature Relaxation?Process on Ultra Low Carbon Bainite Steel Without Nb, Ti and Other Elements. Iron and Steel, 2014, 49(8): 88-93.
Kong J H, Xie C S.Effect of Molybdenum On Continuous Cooling Bainite Transformation Of Low-Carbon Micro Alloyed Steel [J].Materials and Design, 2006, (27):1169-1173
[1]
Kong J H, Xie C S.Effect of Molybdenum On Continuous Cooling Bainite Transformation Of Low-Carbon Micro Alloyed Steel [J].Materials and Design, 2006, (27):1169-1173
Chiou C S，Yhng J R，Huang C Y.The Effect Of Prior Compressive Deformation of Austenite On Toughness Property In An Ultra一Low Carbon Bainitic Steels. Mater [J].Chem Phys, 2001, (69):113-113
[3]
Chiou C S，Yhng J R，Huang C Y.The Effect Of Prior Compressive Deformation of Austenite On Toughness Property In An Ultra一Low Carbon Bainitic Steels. Mater [J].Chem Phys, 2001, (69):113-113
[4]
ParkK T, Kim Y S, Lee J G, Shin D H.Thermal stability and mechanical properties of ultrafine grained low carbon steel[J].Mater. Sc.i & Eng, 2000, A293:165-172
[4]
ParkK T, Kim Y S, Lee J G, Shin D H.Thermal stability and mechanical properties of ultrafine grained low carbon steel[J].Mater. Sc.i & Eng, 2000, A293:165-172
[5]
Shang C J, Zhao Y T, Wang X M, et al.Formation And Control Of The Acicular Ferrite In Low Carbon Micro Alloying steel[J].Materials Science Forum, 2005, 475 - 479:85-88
[5]
Shang C J, Zhao Y T, Wang X M, et al.Formation And Control Of The Acicular Ferrite In Low Carbon Micro Alloying steel[J].Materials Science Forum, 2005, 475 - 479:85-88
[6]
Zhao Y T, Shang C J, Yang S W.The Metastable Transformation In Mo-Nb-Cu-B Low Carbon Steel[J].Mater Sci Eng A, 2006, 433:169-169
[6]
Zhao Y T, Shang C J, Yang S W.The Metastable Transformation In Mo-Nb-Cu-B Low Carbon Steel[J].Mater Sci Eng A, 2006, 433:169-169
[7]
Wang X M, Shang C J, Yang S W, et al .The Refinement Technology For Bainite And Its Application[J].Materials Science and Engineering, 2006, A438-440:162-165
[7]
Wang X M, Shang C J, Yang S W, et al .The Refinement Technology For Bainite And Its Application[J].Materials Science and Engineering, 2006, A438-440:162-165
[8]
Shang C J, Wang X M, Yang S W, et al.Refinement of Packet Size In Low Carbon Bainiti Steel By Special Thermo Mechanical Control Process[J].J Univ Sci Technol Beijing, 2004, 11(3):221-221
[8]
Shang C J, Wang X M, Yang S W, et al.Refinement of Packet Size In Low Carbon Bainiti Steel By Special Thermo Mechanical Control Process[J].J Univ Sci Technol Beijing, 2004, 11(3):221-221
[9]
Shin D H, Kim B C, Park K T, ChooW Y.Microstructural changes in equal channel angular pressed low carbon steel by static annealing[J].ActaMater, 2000, 48:3245-3252.
[9]
Shin D H, Kim B C, Park K T, ChooW Y.Microstructural changes in equal channel angular pressed low carbon steel by static annealing[J].ActaMater, 2000, 48:3245-3252.
[10]
Cheng J S，Wang X M，He X L，et al.A Special TMCP Used To Develop an 800 MPa Grade HSLA Steel[J].Journal Of University Of Science and Technology Beijing, 2001, 8(3):224-228
[10]
Cheng J S，Wang X M，He X L，et al.A Special TMCP Used To Develop an 800 MPa Grade HSLA Steel[J].Journal Of University Of Science and Technology Beijing, 2001, 8(3):224-228
H K SUNG, S Y SHIN, et al.Effects of Cooling Conditions on Microstructure, Tensile Properties, and Charpy Impact Toughness of Low-Carbon High-Strength Bainitic Steels[J].Met. Mater. Int, 2012, 44:294-301
[12]
H K SUNG, S Y SHIN, et al.Effects of Cooling Conditions on Microstructure, Tensile Properties, and Charpy Impact Toughness of Low-Carbon High-Strength Bainitic Steels[J].Met. Mater. Int, 2012, 44:294-301
[13]
Wang X M, He X L, Yang S W, et al.Refining Of Intermediate Transformation Microstructure By Relaxation Processing[J].ISIJ International, 2002, 42(12):1553-1559
[13]
Wang X M, He X L, Yang S W, et al.Refining Of Intermediate Transformation Microstructure By Relaxation Processing[J].ISIJ International, 2002, 42(12):1553-1559
2014, Vol. 49 
