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,910 北京科技大学学报 第29卷 了MC相的溶解和长大.二者的变化将导致奥氏体 参考文献 晶粒尺寸阈值的增大，从而将使奥氏体晶粒平均尺 [1]杨秀亮·加热温度对管线钢第二相粒子固溶及晶粒长大的影 寸增大，在继续延长均热时间到80min的过程中， 响.钢铁钒钛，2002,23(2)：11 MC相颗粒质量分数基本没有变化，但MC相质点 [2]Speer JG.Michael J R.Hansen SS.Carbonitride precipitation 的平均尺寸增大，这相应地也将引起奥氏体晶粒平 in niobium/vanadium microalloyed steels.Metal Trans A.1987. 18(2):211 均尺寸增大 [3]Smith R M,Dunne D P.Structural aspects of alloy carbonitride 根据实验结果和分析可知，1250℃保温45min precipitation microalloyed steels.Mater Forum.1988,11:166 时，钢中基本上已经达到该温度下Ti和Nb的固溶 [4]Hong S G.Kang K B.Park C G.Strain-Induced precipitation of 度积要求，继续延长均热时间对提高Ti和Nb的固 Nb in Nb and NbTi microalloyed HSLA steels.Scripta Mater, 2002,46(2):163 溶度积不具备实际意义，只能导致奥氏体晶粒平均 [5]Edutta B.Valdes E.Scllar C M.Mechanical and kinetics of 尺寸的增大，因此根据实验条件下所得结果认为该 strain induced precipitation of Nb(C.N)in microalloyed austen- 钢种在1250℃进行均热时，均热时间应不大于 ite.Acta Metal Mater.1992,44(4):653 45 min. [6]Poths R M.Higginson RL.Palmiere EJ.Complex precipitation behavior in a microalloyed plate steel.Scpital Mater,2001.44 3结论 (1):147 (1)1250℃、保温时间≤45min时，实验钢中 [7]Craver A J.He K.Garvie L A J.et al.Complex heterogeneous precipitation in TiNb microalloyed Al-killed HSLA steels-I. Nb和Ti的固溶率由55%和78%分别提高到 (Ti.Nb)(C.N)particles.Acta Mater,2000,48(15):3857 64.2%和85.8%，继续延长保温时间二者的固溶率 [8]雍岐龙，马鸣图，吴宝熔。微合金钢一物理和力学治金.北 基本无变化 京：机械工业出版社，1989：254 (2)1250℃、保温时间≤45min时，实验钢中尺 [9]Gladman T.On the theory of the effect of precipitate austenite 寸较小（≤96nm)的未固溶颗粒比例逐渐减少，较大 grain growth in metals.Proc R Soc.1966.266A:298 [10]Gladman T.The effect of second phase particles on grain growth 尺寸（≥300nm)的颗粒比例基本不发生变化.继续 /Hansen N.Jones A R.Leffers T.Recrystallization of Multi- 延长保温时间，较大尺寸的颗粒比例将增加， phase and Particle Containing Materials.Roskilde:Riso National (3)此实验钢在1250℃进行均热时，均热时间 Laboratory.1980:183 应不大于45min, [11]Gladman T.Grain refinement in multiple microalloyed steels/ HSLA Steels.Warrendale:TMS-AIME,1992:3 Effect of soaking time on the dissolution of microalloyed elements in high strength steel containing Ti and Nb XUE Rundong,ZHAO Zhiyi,WANG Mingxia,XIE Jianxin Materials Science and Engineering School.University of Science and Technology Beijing.Beijing 100083.China ABSTRACI Dissolution of carbonitride in high-strength steel containing Ti and Nb was investigated by means of phase analysis and X-ray diffraction.The results show that the precipitation phases are fcc Ti(CN),(TiNb) (CN)and TiC when heated to 1250C without soaking:but mainly Ti(CN)and TiC when heated to 1250C and preserved for 45 min,their size increased from 300nm to 323 nm,and the dissolution rates of Ti and Nb were 64.2%and 85.8%respectively.The content of precipitates extracted from the sample soaked for 80min was almost the same with that for 45 min,whereas the particle size increased.It indicated that the dissolution process was apparently approaching thermodynamic equilibrium. KEY WORDS high-strength steel;carbonitride;soaking time;precipitation phase:X-ray diffraction analysis了 MC 相的溶解和长大．二者的变化将导致奥氏体 晶粒尺寸阈值的增大从而将使奥氏体晶粒平均尺 寸增大．在继续延长均热时间到80min 的过程中 MC 相颗粒质量分数基本没有变化但 MC 相质点 的平均尺寸增大这相应地也将引起奥氏体晶粒平 均尺寸增大． 根据实验结果和分析可知1250℃保温45min 时钢中基本上已经达到该温度下 Ti 和 Nb 的固溶 度积要求继续延长均热时间对提高 Ti 和 Nb 的固 溶度积不具备实际意义只能导致奥氏体晶粒平均 尺寸的增大．因此根据实验条件下所得结果认为该 钢种在1250℃进行均热时均热时间应不大于 45min． 3 结论 （1）1250℃、保温时间≤45min 时实验钢中 Nb 和 Ti 的固溶率由 55％ 和 78％ 分 别 提 高 到 64∙2％和85∙8％继续延长保温时间二者的固溶率 基本无变化． （2）1250℃、保温时间≤45min 时实验钢中尺 寸较小（≤96nm）的未固溶颗粒比例逐渐减少较大 尺寸（≥300nm）的颗粒比例基本不发生变化．继续 延长保温时间较大尺寸的颗粒比例将增加． （3） 此实验钢在1250℃进行均热时均热时间 应不大于45min． 参 考 文 献 ［1］ 杨秀亮．加热温度对管线钢第二相粒子固溶及晶粒长大的影 响．钢铁钒钛200223（2）：11 ［2］ Speer J GMichael J RHansen S S．Carbonitride precipitation in niobium／vanadium microalloyed steels．Metal Trans A1987 18（2）：211 ［3］ Smith R MDunne D P．Structural aspects of alloy carbonitride precipitation microalloyed steels．Mater Forum198811：166 ［4］ Hong S GKang K BPark C G．Strain-Induced precipitation of Nb in Nb and Nb—Ti microalloyed HSLA steels．Scripta Mater 200246（2）：163 ［5］ Edutta BValdes EScllar C M．Mechanical and kinetics of strain induced precipitation of Nb（CN） in microalloyed austenite．Acta Metal Mater199244（4）：653 ［6］ Poths R MHigginson R LPalmiere E J．Complex precipitation behavior in a microalloyed plate steel．Scpital Mater200144 （1）：147 ［7］ Craver A JHe KGarvie L A Jet al．Complex heterogeneous precipitation in Ti—Nb microalloyed Al—killed HSLA steels—Ⅰ （TiNb）（CN） particles．Acta Mater200048（15）：3857 ［8］ 雍岐龙马呜图吴宝熔．微合金钢———物理和力学冶金．北 京：机械工业出版社1989：254 ［9］ Gladman T．On the theory of the effect of precipitate austenite grain growth in metals．Proc R Soc1966266A：298 ［10］ Gladman T．The effect of second phase particles on grain growth ∥Hansen NJones A RLeffers T．Recrystallization of Multiphase and Particle Containing Materials．Roskilde：Riso National Laboratory1980：183 ［11］ Gladman T．Grain refinement in multiple microalloyed steels∥ HSLA Steels．Warrendale：T MS—AIME1992：3 Effect of soaking time on the dissolution of microalloyed elements in high-strength steel containing Ti and Nb XUE RundongZHAO ZhiyiWA NG MingxiaXIE Jianxin Materials Science and Engineering SchoolUniversity of Science and Technology BeijingBeijing100083China ABSTRACT Dissolution of carbonitride in high-strength steel containing Ti and Nb was investigated by means of phase analysis and X-ray diffraction．The results show that the precipitation phases are fcc Ti（CN）（TiNb） （CN） and TiC when heated to1250℃ without soaking；but mainly Ti（CN） and TiC when heated to1250℃ and preserved for45mintheir size increased from 300nm to 323nmand the dissolution rates of Ti and Nb were64∙2％ and85．8％ respectively．The content of precipitates extracted from the sample soaked for80min was almost the same with that for45minwhereas the particle size increased．It indicated that the dissolution process was apparently approaching thermodynamic equilibrium． KEY WORDS high-strength steel；carbonitride；soaking time；precipitation phase；X-ray diffraction analysis ·910· 北 京 科 技 大 学 学 报 第29卷