覃展鹏,王红鸿,童志,胡锋,李丽,吴开明

• 1:省部共建耐火材料与冶金国家重点实验室高性能钢铁材料及其应用湖北省协同创新中心武汉科技大学
• 2:南京钢铁集团有限公司研究院

摘要(Abstract)：

对低合金高强钢分别进行淬火+回火(QT)热处理和淬火+两相区的亚温淬火+回火(QLT)三段式热处理,采用光学显微镜(OM)、扫描电镜(SEM)、电子背散射衍射(EBSD)方法等观察分析其显微组织形貌、组成相和大角度晶界的密度分布,并测试其力学性能。结果表明:相比于QT工艺,低合金高强钢在QLT工艺后,强度虽稍有下降,但低温冲击韧性显著提高,而且屈强比降低,表现出良好的综合力学性能。在发生奥氏体逆转变以及两相区等温过程中,亚温淬火工艺细化新生成的奥氏体晶粒尺寸、增加大角度晶界密度,使有效晶粒尺寸明显减小,残留奥氏体的含量明显增加。

关键词(KeyWords)： 亚温淬火;低合金高强钢;低温冲击韧性;有效晶粒尺寸;逆转变奥氏体

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 覃展鹏,王红鸿,童志,胡锋,李丽,吴开明

DOI: 10.13289/j.issn.1009-6264.2017-0085

参考文献(References)：

• [1]张晓刚.近年来低合金高强度钢的进展[J].钢铁,2012,46(11):1-9.ZHANG Xiao-gang.Development of high strength low alloy steel in recent years[J].Iron and Steel,2012,46(11):1-9.
• [2]侯家平,潘涛,朱莹光,等.临界淬火工艺对9Ni低温钢力学性能及精细组织的影响[J].材料热处理学报,2014,35(10):88-91.HOU Jia-ping,PAN Tao,ZHU Ying-guang,et al.Effect of inter-critical quenching process on mechanical property and microstructure of 9Ni cryogenic steel[J].Transactions of Materials and Heat Treatment,2014,35(10):88-91.
• [3]吴玉萍,肖昌利.低合金钢亚温淬火强韧化研究[J].理化检验:物理分册,1997(2):11-13.WU Yu-ping,XIAO Chang-li.Study of the strengthening and toughness of low-alloy steel after subnormal temperature quenching[J].Physical Testing and Chemical Analysis Part A:Physical Testing,1997(2):11-13.
• [4]Liu Q D,Wen H M,Zhang H,et al.Effect of multistage heat treatment on microstructure and mechanical properties of high-strength low-alloy steel[J].Metallurgical and Materials Transactions A,2016,47(5):1960-1974.
• [5]Xie Z J,Yuan S F,Zhou W H,et al.Stabilization of retained austenite by the two-step inter-critical heat treatment and its effect on the toughness of a low alloyed steel[J].Materials and Design,2014,59:193-198.
• [6]Xie Z J,Han G,Zhou W H,et al.Study of retained austenite and nano-scale precipitation and their effects on properties of a low alloyed multi-phase steel by the two-step inter-critical treatment[J].Materials Characterization,2016,113:60-66.
• [7]罗小兵,杨才福,柴锋,等.两相区二次淬火对高强度船体钢低温韧性的影响[J].金属热处理,2012,37(9):71-74.LUO Xiao-bing,YANG Cai-fu,CHAI Feng,et al.Effect of inter-critical quenching on low temperature toughness of high strength ship hull steel[J].Heat Treatment of Metals,2012,37(9):71-74.
• [8]史学星,杨才福,沈俊昶,等.两相区淬火对10Ni5Cr Mo钢组织与性能的影响[J].金属热处理,2008,33(4):31-35.SHI Xue-xing,YANG Cai-fu,SHEN Jun-chang,et al.Effect of inter-critical quenching on microstructure and properties of 10Ni5Cr Mo steel[J].Heat Treatment of Metals,2008,33(4):31-35
• [9]Clarke A J,Speer J G,Matlock D K,et al.Influence of carbon partitioning kinetics on final austenite fraction during quenching and partitioning[J].Scripta Material,2009,61(2):149-152.
• [10]Dhua S K,Mukerjee D,Sarma D S.Influence of tempering on the microstructure and mechanical properties of HSLA-100 steel plates[J].Metallurgical and Materials Transactions A,2001,32(9):2259-2270.
• [11]Pan T,Zhu J,Yang C F,et al.Kinetics simulation and experimental observation of fine microstructure of 9%Ni cryogenic steel processed by QLT heat treatment[J].Chinese Science Bulletin,2014,59(15):1765-1772.
• [12]古原忠.钢中马氏体和贝氏体基体组织的特征[J].热处理,2009,24(2):16-21.Furuhara T.Matrix structure of martensite and bainite in steels[J].Heat Treatment,2009,24(2):16-20.
• [13]沈俊昶,杨才福,张永权.两相区淬火对5Ni Cr Mo钢组织与性能的影响[J].钢铁,2007,42(6):63-68.SHEN Jun-chang,YANG Cai-fu,ZHANG Yong-quan.The effect of inter-critical treatment on the structure and properties of 5Ni Cr Mo stee I[J].Iron and Steel,2007,42(6):63-68.
• [14]Moritoa S,Yoshidab H,Makic T,et al.Effect of block size on the strength of lath martensite in low carbon steels[J].Materials Science and Engineering A,2006,438-440(25):237-240.
• [15]Inoue T,Matsuda S,Okamura Y,et al.The fracture of a low carbon tempered martensite[J].Transactions of the Japan Institute of Metals,1970,11(1):36-43.
• [16]沈俊昶,罗志俊,杨才福,等.低合金钢板条组织中影响低温韧性的“有效晶粒尺寸”[J].钢铁研究学报,2014,26(7):70-76.SHEN Jun-chang,LUO Zhi-jun,YANG Cai-fu,et al.“Effective grain size”affecting low temperature toughness in lath structure of HSLA Steel[J].Journal of Iron and Steel Research,2014,26(7):70-76.
• [17]Hoshino M,Saitoh N,Muraoka H,et al.Development of super-9%Ni steel plates with superior low-temperature toughness for LNG storage tanks[J].Nippon Steel Technical Report,2004,90:20-24.
• [18]Kim J.The mechanism of microstructrual change and its consequences in a low carbon Fe-6Ni alloy[D].Berkeley(U.S.),University of California,Berkeley,1979:19-37.
• [19]Jang J I,Ju J B,Lee B W,et al.Effects of microstructural change on fracture characteristics in coarse-grained heat-affected zones of QLT-processed9%Ni steel[J].Materials Science and Engineering A,2003,340(1),68-79.
• [20]钟宁.高强度Q&P钢和Q-P-T钢的研究[D].上海:上海交通大学,2009.ZHONG Ning.Research on high strength Q&P and Q-P-T steels[D].Shanghai:Shanghai Jiao Tong University,2009.
• [21]De Knijf D,Petrov R,F9jer C,et al.Effect of fresh martensite on the stability of retained austenite in quenching and partitioning steel[J].Materials Science and Engineering A,2014,615:107-115.
• [22]Han J,da Silva A K,Ponge D,et al.The effects of prior austenite grain boundaries and microstructural morphology on the impact toughness of intercritically annealed medium Mn steel[J].Acta Materialia,2017,122:199-206.
• [23]Takahiro K,Akio O,Osamu T.Properties of high toughness 9%Ni heavy section steel plate and it’s applicability to 200000kl LNG storage tanks[J].Kawasaki Steel Technical Repor,1999,40:72-79.
• [24]Akhiate A,Braud E,Thibault D,et al.Carbon content and heat treatment effects on microstructures and mechanical properties of 13%Cr-4%Ni martensitic stainless steel[C]∥Conference of Metallurgist,Vancouver,2014:1-10.
• [25]Seol J B,Jung J E,Jang Y W,et al.Influence of carbon content on the microstructure,martensitic transformation and mechanical properties in austenite/ε-martensite dual-phase Fe-Mn-C steels[J].Acta Materialia,2013,61(2):558-578.
• [26]Vignal V,Ringeval S,Thiébaut S,et al.Influence of the microstructure on the corrosion behaviour of low-carbon martensitic stainless steel after tempering treatment[J].Corrosion Science,2014,85:42-51.

文章评论(Comment)：