采用VN16和FeV80两种钒微合金化方式冶炼了4种不同钒、氮含量的试验钢,研究了钒、氮含量对高强度热轧钢板微观组织和强韧性的影响。结果表明,试验钢的微观组织均为铁素体+珠光体,在氮含量很低的情况下,钒微合金化钢的铁素体晶粒较粗大,增钒虽能细化铁素体晶粒,但细化程度并不大;钒氮微合金化钢的铁素体晶粒较细小,增氮能明显细化铁素体晶粒,氮含量越高,细化程度就越大,氮含量是影响铁素体晶粒细化的主要因素。在钒微合金化钢中,第二相颗粒主要在铁素体中析出,起到强烈的析出强化作用,细晶强化作用相对较弱,造成增钒时钢的强度明显提高,而韧塑性有所降低;在钒氮微合金化钢中,增氮能有效促进第二相颗粒在奥氏体中的析出,明显增强钒的细晶强化作用,减弱析出强化作用,使钢的强度得到提高的同时,韧塑性也有所提高,氮含量越高,这种强化效果就越显著。
Four kinds of test steels with different vanadium and nitrogen contents were smelted and cast by VN16 and FeV80 vanadium microalloying method. The effects of vanadium and nitrogen contents on the microstructure, strength and toughness of high strength hot-rolled steel plate were studied. The results show that the microstructure of test steels is ferrite and pearlite. When the nitrogen content is very low, the ferrite grain of vanadium microalloyed steel is coarse. Although increasing vanadium can refine the ferrite grain, the degree of refinement is not large. The ferrite grain of vanadium-nitrogen microalloyed steel is fine, and the increase of nitrogen can obviously refine the ferrite grain. The higher the nitrogen content, the greater the refinement degree. The nitrogen content is the main factor affecting the ferrite grain refinement. In vanadium microalloyed steel, the second phase particles are mainly precipitated in ferrite, which plays a strong role in precipitation strengthening, and the fine grain strengthening is relatively weak, resulting in the obvious increase of steel strength and decrease of toughness and plasticity when vanadium is added. In vanadium-nitrogen microalloyed steel, increasing nitrogen can effectively promote the precipitation of second phase particles in austenite, significantly enhance the fine grain strengthening effect of vanadium and weaken the precipitation strengthening effect, resulting in the improvement of steel strength, toughness and plasticity. The higher the nitrogen content, the more significant the strengthening effect.
[1] 刘清梅, 封娇洁 . 汽车轻量化条件下先进高强钢的发展及现状[J]. 轧钢, 2020, 37(4): 65-70.
[2] 魏振洋 . 汽车轻量化技术的研究现状[J]. 汽车工程师, 2020(11): 11-12.
[3] Rune L, Bevis H, Tadeusz S, 等. 钒在微合金化钢中的作用[M]. 杨才福, 王瑞珍, 陈雪慧, 译 . 北京: 冶金工业出版社, 2015.
[4] 杨才福, 罗小兵 . 钒氮微合金钢的研发与应用[J]. 世界金属导报, 2016, B12: 1-9.
[5] 柴峰, 师仲然, 杨才福, 等. 氮对钒微合金钢粗晶热影响区(CGHAZ)的组织和性能的影响[J]. 材料研究学报, 2019, 33(11): 848-855.
[6] 齐俊杰, 黄运华, 张跃. 微合金化钢[M]. 北京: 冶金工业出版社, 2006.
[7] 王有铭, 李曼云, 韦光 . 钢材的控制轧制和控制冷却技术[M]. 北京: 冶金工业出版社, 2009.
[8] 杨吉春, 田时雨, 余海存, 等 . 氮对含钒 Q345 钢组织和力学性能的影响[J]. 钢铁钒钛, 2019, 40(1): 125-139.
[9] 马江南, 杨才福, 王瑞珍 . 增氮对钒微合金钢组织和性能的影响[J]. 钢铁, 2015, 50(4): 63-69.
[10] 杜杰杰, 孙志林, 张昕, 等 . 氮对高强度钢筋用钒微合金化钢冲击韧度的影响[J]. 热处理, 2018, 33(4): 18-23.
[11] 国家标准化管理委员会 . GB/T 228.1—2010 金属材料拉伸试验 第1部分: 室温试验方法[S]. 北京: 中国标准出版社, 2010.
[12] 国家标准化管理委员会 . GB/T 229—2020 金属材料夏比摆锤冲击试验方法[S]. 北京: 中国标准出版社, 2020.
[13] 崔英和, 张文才, 张冬梅, 等 . 热轧工艺参数对含钒微合金钢的组织性能的影响[J]. 钢铁研究, 2005(4): 45-49.
[14] Glisic D, Radovic N, Koprivica A, et al. Influence of reheating temperature and Vanadium content on transformation behavior and mechanical properties of medium carbon forging steels[J]. ISIJ International, 2010, 50(4): 601-606.
[15] Ishikawa F, Takahashi T. The formation of intragranular ferrite plates in medium-carbon steels for hot-forging and its effect on the toughness[J]. ISIJ International, 1995, 35(9): 1128-1133.
[16] 雍岐龙. 钢铁材料中的第二相[M]. 北京: 冶金工业出版社, 2006.
[17] 柳书平, 杨才福, 张永权. 氮对钒钢性能及析出相的影响[J]. 金属热处理, 2001, 26(10): 7-9.
[18] 杨才福, 张永权, 柳书平. 钒氮微合金化钢筋的强化机制[J]. 钢铁, 2001(5): 55-57.
[19] Zajac S. Precipitation and grain refinement in vanadium-containing steels[C]//International Symposium 2001 on Vanadium Application Technology. Beijing, 2001: 62-68.
[20] Baker T N. Processes, microstructure and properties of vanadium microalloyed steels[J]. Metal Science Journal, 2014, 25(9): 1083-1107.
[21] 雍岐龙, 马明图, 吴宝榕 . 微合金钢-物理和力学冶金[M]. 北京: 机械工业出版社, 1989.
[22] 戚正风 . 金属热处理原理[M]. 北京: 机械工业出版社1989.
[23] 孙邦明, 季怀忠, 杨才福, 等 . V-N 微合金化钢筋中钒的析出行为[J]. 钢铁, 2001, 36(2): 44-47.