屈服强度1100 MPa级超高强钢热处理组织及性能
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摘要
随着工程机械向大型化轻量化方向发展,超高强钢的市场需求越来越大且综合性能要求越来越严格。结合5 000 mm宽厚板生产线及热处理装备,研究淬火过程中淬火温度对屈服强度1 100 MPa级超高强度钢组织及力学性能的影响。结果表明,淬火温度决定了合金元素的溶解和分布状态、原始奥氏体晶粒尺寸,影响试验钢的综合力学性能。不同淬火温度下,基本微观组织为板条马氏体。随着淬火温度的升高,原奥氏体晶粒尺寸增大;当淬火温度由840℃升高至990℃时,原奥氏体晶粒平均尺寸由9.0μm增加到22.5μm。采用900～930℃淬火及350℃回火的热处理工艺,试验钢可获得最佳的强韧性匹配,此时屈服强度为1 125～1 155 MPa、抗拉强度为1 306～1 335 MPa、断后伸长率为12.5%～14.0%,布氏硬度为415～419,-40℃冲击功为80～100 J,抗拉强度与布氏硬度比值范围在3.10～3.20之间,满足标准GB/T 28909—2012对Q1100E的要求。
With the development of construction machinery steel towards large-scale and lightweight, the market demand of ultra-high strength steel has been increasing and requirements for its comprehensive properties get more and more strict. The production line and heat treatment equipment of 5 000 mm wide plate were employed to investigate the effects of quenching temperature on the microstructures and mechanical properties of 1 100 MPa grade ultra-high strength steel. Results show that the dissolution and distribution of alloying elements, the grain size of primary austenite, and the mechanical properties of experimental steel are determined by the quenching temperature. At different quenching temperatures, the basic microstructures of experimental steels are all lath martensite. As quenching temperatures increasing, the grain size of primary austenite gradually increases. When the quenching temperature increases from 840 ℃ to 990 ℃, the average grain size of primary austenite is increased from 9.0 μm to 22.5 μm. By adopting the heat treatment processes of quenching at 900-930 ℃ and tempering at 350 ℃, the best combination of strength and toughness of experimental steel can be achieved: With yield strength of 1 125-1 155 MPa, tensile strength of 1 306-1 335 MPa, elongation of 12.5%-14.0%, Brinell hardness of 415-419, impact toughness at-40 ℃ of 80-100 J, and the ratio of tensile strength and Brinell hardness of 3.10-3.20, the experimental steel can meet the requirements of GB/T 28909-2012 for Q1100 E.
With the development of construction machinery steel towards large-scale and lightweight, the market demand of ultra-high strength steel has been increasing and requirements for its comprehensive properties get more and more strict. The production line and heat treatment equipment of 5 000 mm wide plate were employed to investigate the effects of quenching temperature on the microstructures and mechanical properties of 1 100 MPa grade ultra-high strength steel. Results show that the dissolution and distribution of alloying elements, the grain size of primary austenite, and the mechanical properties of experimental steel are determined by the quenching temperature. At different quenching temperatures, the basic microstructures of experimental steels are all lath martensite. As quenching temperatures increasing, the grain size of primary austenite gradually increases. When the quenching temperature increases from 840 ℃ to 990 ℃, the average grain size of primary austenite is increased from 9.0 μm to 22.5 μm. By adopting the heat treatment processes of quenching at 900-930 ℃ and tempering at 350 ℃, the best combination of strength and toughness of experimental steel can be achieved: With yield strength of 1 125-1 155 MPa, tensile strength of 1 306-1 335 MPa, elongation of 12.5%-14.0%, Brinell hardness of 415-419, impact toughness at-40 ℃ of 80-100 J, and the ratio of tensile strength and Brinell hardness of 3.10-3.20, the experimental steel can meet the requirements of GB/T 28909-2012 for Q1100 E.
引文
[1] 宋欣,王根矶,张国栋,等.厚规格调质高强钢Q890的研制与开发[J].材料热处理学报,2014,35(8):147.(Song X,Wang G J,Zhang G D,et al.Research and development of heavy gauge quenching and tempering high strength Q890 steel[J].Transactions of Materials and Heat Treatment,2014,35(8):147.)
[2] Zhen F,Zhang K,Guo Z L,et al.Effect of martensite fine structure on mechanical properties of an 1 100 MPa grade ultra-high strength steel[J].Journal of Iron and Steel Research International,2015,22(7):645.
[3] 胡光立,谢希文.钢的热处理-原理和工艺[M].西安:西北工业大学出版社,1993.(Hu G L,Xie X W.Heat Treatment of Steel-Principle and Process[M].Xi’an:Northwest Polytechnic University Press,1993.)
[4] 李大赵,崔天燮,王育田,等.低碳低合金高强贝氏体钢的研究现状及进展[J].钢铁研究学报,2014,25(11):2.(Li D Z,Cui T X,Wang Y T,et al.Status and development of low carbon microalloying bainitic high strength steel[J].Journal of Iron and Steel Research,2014,25(11):2.)
[5] 刘伟建,李晶霍,向东.高强度低合金耐磨钢NM400的强韧化机制[J].钢铁研究学报,2014,26(7):81.(Liu W J,Li J H,Xiang D.Mechanism of strengthening and toughening for wear resistant steel NM400 with high strength and low alloy[J].Journal of Iron and Steel Research,2014,26(7):81.)
[6] Morito S,Saito H,Ogawa T,et al.Effect of austenite grain size on the morphology and crystallography of lath martensite in low carbon steels[J].ISIJ International,2005,45:91.
[7] Speich G R.Intercritical austenization of two Fe-Mn-C steels[J].Metallurgical Transactions,1981,12A:1419.
[8] Maropoulos S,Ridley N,Karagiannis S.Structural variations in heat treated low alloy steel forgings[J].Materials Science and Engineering,2004,380A(1/2):79.
[9] Stasko R,Adrian H,Adrian A.Effect of nitrogen and vanadium on austenite grain growth kinetics of a low alloy steel[J].Materials Characterization,2006,56(4/5):340.
[10] Stasko R,Adrian H,Adrian A.Effect of nitrogen and vanadium on austenite grain growth kinetics of a low alloy steel[J].Materials Characterization,2006,56:341.
[11] 沈保罗,李莉,岳昌林.钢铁材料抗拉强度与硬度关系综述[J].现代铸铁,2012(1):95.(Shen B L,Li L,Yue C L.Summarization of relationship between tensile strength and hardness of iron-steel materials[J].Modern Cast Iron,2012(1):95.)
[12] 李亚欣,刘雅政,洪斌,等.P110 级石油套管淬火组织形态对残余应力的影响[J].钢铁研究学报,2010,22(8):55.(Li Y X,Liu Y Z,Hong B,et al.Effect of quenching microstructure morphology on residual stress of P110 oil casing[J].Journal of Iron and Steel Research,2010,22(8):55.)
[13] 唐明华,刘志义,胡双开,等.ZrC/奥氏体相界面形变诱导相变动力学[J].中南大学学报:自然科学版,2010,41(1):120.(Tang M H,Liu Z Y,Hu S K,et al.Transitional dynamics of deformation induced phase transformation at ZrC/austenitic interface[J].Journal of Central South University:Science and Technology,2010,41(1):120.)
[14] Carlson M F,Narasimha B V,Thomas G.The effect of austenitzing temperature upon the microstructure and mechanical properties of experimental Fe/Cr/C steels[J].Metallurgical Transactions,1979,10A(9):1273.
[15] Morito S,Saito H,Ogawa T,et al.Effect of austenite grain size on the morphologt and crystallography of lath martensite in low carbon steels[J].ISIJ International,2005,45(1):91.
[16] 崔忠圻,覃耀春.金属学与热处理[M].北京:机械工业出版社,2011.(Cui Z X,Qin Y C.Metallography and Heat Treatment[M].Beijing:Mechanical Industry Press,2011.)
[17] 惠卫军,董翰,王毛球,等.淬火温度对Cr-Mo-V系低合金高强度钢力学性能的影响[J].金属热处理,2002,27(3):14.(Hui W J,Dong H,Wang M Q,et al.Influence of quenching temperature on mechanical properties of low alloy high strength Cr-Mo-V steel[J].Heat Treatment of Metals,2002,27(3):14.)
[18] 杨景红,薛钢,蒋颖,等.Acl附近临界区处理对785 MPa级船体钢屈强比的影响[J].材料热处理学报,2014,35(3):117.(Yang J H,Xue G,Jiang Y,et al.Effect of tempering temperature and time on yield ratio of a 785 MPa grade hull steel[J].Transactions of Materials and Heat Treatment,2014,35(3):117.)
[19] Nohava J,Hausild P,Karlik M,et al.Electron backscattering diffraction analysis of secondary cleavage cracks in a reactor pressure vessel steel[J].Materials Characterization,2003,49(3):211.
[20] Luo Z J,Shen J C,Su H,et al.Effect of substructure on toughness of lath martensite/bainite mixed structure in low-carbon steels[J].Journal of Iron and Steel Research International,2010,17(11):40.
[21] Law N C,Edmonds D V.The formation of austenite in a low-alloy steel[J].Metallurgical Transactions,1980,11A(1):33.
[22] 房玉佩,谢振家,尚成嘉.感应回火对1 000 MPa级高强度低合金钢碳化物析出行为及韧性的影响[J].金属学报,2014,50(12):1419.(Fang Y P,Xie Z J,Shang C J.Effect of induction tempering on carbide precipitation behavior and toughness of a 1 000 MPa grade high strength low alloy steel[J].Acta Metallurgica Sinica,2014,50(12):1419.)
[2] Zhen F,Zhang K,Guo Z L,et al.Effect of martensite fine structure on mechanical properties of an 1 100 MPa grade ultra-high strength steel[J].Journal of Iron and Steel Research International,2015,22(7):645.
[3] 胡光立,谢希文.钢的热处理-原理和工艺[M].西安:西北工业大学出版社,1993.(Hu G L,Xie X W.Heat Treatment of Steel-Principle and Process[M].Xi’an:Northwest Polytechnic University Press,1993.)
[4] 李大赵,崔天燮,王育田,等.低碳低合金高强贝氏体钢的研究现状及进展[J].钢铁研究学报,2014,25(11):2.(Li D Z,Cui T X,Wang Y T,et al.Status and development of low carbon microalloying bainitic high strength steel[J].Journal of Iron and Steel Research,2014,25(11):2.)
[5] 刘伟建,李晶霍,向东.高强度低合金耐磨钢NM400的强韧化机制[J].钢铁研究学报,2014,26(7):81.(Liu W J,Li J H,Xiang D.Mechanism of strengthening and toughening for wear resistant steel NM400 with high strength and low alloy[J].Journal of Iron and Steel Research,2014,26(7):81.)
[6] Morito S,Saito H,Ogawa T,et al.Effect of austenite grain size on the morphology and crystallography of lath martensite in low carbon steels[J].ISIJ International,2005,45:91.
[7] Speich G R.Intercritical austenization of two Fe-Mn-C steels[J].Metallurgical Transactions,1981,12A:1419.
[8] Maropoulos S,Ridley N,Karagiannis S.Structural variations in heat treated low alloy steel forgings[J].Materials Science and Engineering,2004,380A(1/2):79.
[9] Stasko R,Adrian H,Adrian A.Effect of nitrogen and vanadium on austenite grain growth kinetics of a low alloy steel[J].Materials Characterization,2006,56(4/5):340.
[10] Stasko R,Adrian H,Adrian A.Effect of nitrogen and vanadium on austenite grain growth kinetics of a low alloy steel[J].Materials Characterization,2006,56:341.
[11] 沈保罗,李莉,岳昌林.钢铁材料抗拉强度与硬度关系综述[J].现代铸铁,2012(1):95.(Shen B L,Li L,Yue C L.Summarization of relationship between tensile strength and hardness of iron-steel materials[J].Modern Cast Iron,2012(1):95.)
[12] 李亚欣,刘雅政,洪斌,等.P110 级石油套管淬火组织形态对残余应力的影响[J].钢铁研究学报,2010,22(8):55.(Li Y X,Liu Y Z,Hong B,et al.Effect of quenching microstructure morphology on residual stress of P110 oil casing[J].Journal of Iron and Steel Research,2010,22(8):55.)
[13] 唐明华,刘志义,胡双开,等.ZrC/奥氏体相界面形变诱导相变动力学[J].中南大学学报:自然科学版,2010,41(1):120.(Tang M H,Liu Z Y,Hu S K,et al.Transitional dynamics of deformation induced phase transformation at ZrC/austenitic interface[J].Journal of Central South University:Science and Technology,2010,41(1):120.)
[14] Carlson M F,Narasimha B V,Thomas G.The effect of austenitzing temperature upon the microstructure and mechanical properties of experimental Fe/Cr/C steels[J].Metallurgical Transactions,1979,10A(9):1273.
[15] Morito S,Saito H,Ogawa T,et al.Effect of austenite grain size on the morphologt and crystallography of lath martensite in low carbon steels[J].ISIJ International,2005,45(1):91.
[16] 崔忠圻,覃耀春.金属学与热处理[M].北京:机械工业出版社,2011.(Cui Z X,Qin Y C.Metallography and Heat Treatment[M].Beijing:Mechanical Industry Press,2011.)
[17] 惠卫军,董翰,王毛球,等.淬火温度对Cr-Mo-V系低合金高强度钢力学性能的影响[J].金属热处理,2002,27(3):14.(Hui W J,Dong H,Wang M Q,et al.Influence of quenching temperature on mechanical properties of low alloy high strength Cr-Mo-V steel[J].Heat Treatment of Metals,2002,27(3):14.)
[18] 杨景红,薛钢,蒋颖,等.Acl附近临界区处理对785 MPa级船体钢屈强比的影响[J].材料热处理学报,2014,35(3):117.(Yang J H,Xue G,Jiang Y,et al.Effect of tempering temperature and time on yield ratio of a 785 MPa grade hull steel[J].Transactions of Materials and Heat Treatment,2014,35(3):117.)
[19] Nohava J,Hausild P,Karlik M,et al.Electron backscattering diffraction analysis of secondary cleavage cracks in a reactor pressure vessel steel[J].Materials Characterization,2003,49(3):211.
[20] Luo Z J,Shen J C,Su H,et al.Effect of substructure on toughness of lath martensite/bainite mixed structure in low-carbon steels[J].Journal of Iron and Steel Research International,2010,17(11):40.
[21] Law N C,Edmonds D V.The formation of austenite in a low-alloy steel[J].Metallurgical Transactions,1980,11A(1):33.
[22] 房玉佩,谢振家,尚成嘉.感应回火对1 000 MPa级高强度低合金钢碳化物析出行为及韧性的影响[J].金属学报,2014,50(12):1419.(Fang Y P,Xie Z J,Shang C J.Effect of induction tempering on carbide precipitation behavior and toughness of a 1 000 MPa grade high strength low alloy steel[J].Acta Metallurgica Sinica,2014,50(12):1419.)