共查询到19条相似文献,搜索用时 109 毫秒
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通过对薄板坯高温变形奥氏体再结晶和未再结晶区变形的有效控制,在包钢CSP生产线上成功地开发出了Nb微合金化汽车大梁用高强度钢带QStE380TM、FAS355L。分析表明,开发的含Nb钢带组织细小、均匀,具有优异的韧性和成形性能,其性能完全满足汽车车箱纵梁、横梁的冲压和装配要求。 相似文献
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介绍了汽车用超深冲热镀锌钢带DC54D+Z、DC56D+Z的研发机理,开发过程中化学成分、热连轧关键工艺参数、冷轧和连续退火工艺的设计及控制。大批量生产实践表明:产品化学成分稳定,具有优良的力学性能、冲压成形性能、焊接性能、耐腐蚀性能,产品广泛应用于汽车的各种覆盖件及零部件。 相似文献
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汽车外面板用高强度钢板 总被引:2,自引:0,他引:2
利用Nb(C、N)的微细析出物和晶粒细化机理,开发出了具有优良成形性能的汽车外面板用SFG(超细晶)高强度钢.钢中的Nb析出物呈现出目前薄板中所没有的特殊析出形态,并且在晶界附近,有形成PFZ(无析出物区)析出物缺乏层的趋势.由于PFZ的存在,虽然晶粒细小,但也显示出了低屈服强度.另外,r-值也比传统钢高,由于添加了B,使钢板显示出优良的抗二次加工脆性.模拟实际的冲压工艺,采用汽车前挡板的金属冲模进行冲压试验,其结果表明,该开发钢比传统钢具有更宽的成形范围.实践证明,该钢具有优良的成形性能. 相似文献
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微合金化控轧控冷钢筋纵向金相组织研究 总被引:1,自引:0,他引:1
对微合金化控轧控冷钢筋的纵向金相组织进行了研究,并分析了不同成分试验钢纵向“条带”组织的差异及形成原因。研究结果表明:偏析元素(P、Si、Mn等)在轧制过程中沿轧制方向呈条状分布,是20MnSi、20MnSiV钢产生带状组织的原因。铌及其碳氮化物的溶质拖曳和“钉扎”作用,使20MnSiNb钢的奥氏体未再结晶轧制温度提高到1050℃,在冷却过程中,先共析铁素体在形变奥氏体晶界和内部变形带均匀析出,随后沿形变奥氏体晶界(在先共析铁素体与奥氏体的界面上)生成珠光体带,最后在形变奥氏体晶粒内部形成贝氏体条。研究条件下优势形核点的排序为:形变奥氏体晶界和形变奥氏体晶内变形带、偏析元素和夹杂、再结晶奥氏体晶界。 相似文献
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The effect of Nb concentration on the transformation from austenite to bainitic ferrite has been examined under simulated strip casting conditions. Nb concentration was found to delay the nucleation of bainite, but accelerated its growth. It is suggested that the delay in nucleation increases the driving force for transformation, which results in an increase in the growth rate of the bainite. The bainite/austenite interfaces are proposed to move too quickly to suffer appreciable solute drag. 相似文献
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The microstructural evolution during the hot rolling of coarse grain sized austenite has been modeled considering all the microstructural mechanisms (dynamic, static and metadynamic recrystallization, strain induced precipitation) that can take place during an industrial TSDR production of three Nb microalloyed steels. Based on the results obtained from the model, processing maps have been drawn for 0.02%, 0.035% and 0.05% Nb microalloyed steels. Optimum processing conditions to exploit all the benefits of the Nb microalloying have been defined considering a final gauge thickness range between 1.5 and 12.65 mm. In addition, and facing the difficulties present in the production of thick hot strip, several alternative thermomechanical schedules are proposed, which would originate microstructures with a suitable combination of homogeneity and retained strain prior to transformation. 相似文献
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通过Nb、V微合金化技术,在CSP产线研制高级别汽车大梁用热轧钢带590L、610L。研制结果表明,以此工艺生产的590L、610L,表面质量好,尺寸精度高,性能稳定,完全满足客户要求。 相似文献
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化学成分和热处理工艺是影响TRIP钢力学性能的关键因素。通过热模拟试验方法研究了不同成分试验钢在临界区退火过程中的微观组织变化规律。结果表明:随着两相区退火温度的升高,铁素体平均晶粒尺寸逐渐减小,铁素体体积分数随着加热温度的升高而降低;残余奥氏体量和其中的C质量分数先随着退火温度的升高而降低,达到一个低谷以后,再随退火温度的升高而升高;在相同的退火温度下,随着Nb的加入,多边形铁素体晶粒尺寸细化,铁素体体积分数逐渐减少;既加Nb又高Si的试验钢钢中残奥数量最多,不加Nb的试验钢中残奥数量最少。TRIP钢试制结果表明,钢带组织类型为典型的TRIP钢组织,多边形铁素体平均晶粒尺寸约8μm,体积分数67%,残余奥氏体体积分数为5.58%,残余奥氏体中C质量分数为1.34%,同时,力学性能也完全满足TRIP590的性能要求。 相似文献
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S. Yu. Nastich E. V. Shul’ga I. V. Lyasotskii D. L. D’yakonov 《Steel in Translation》2012,41(12):1040-1046
Deposits of the carbonitrides (Ti, Nb)(C, N), Nb(C, N), and (Nb, V)(C, N) in the austenite and ferrite phases of X70 steel
sheet after thermomechanical treatment are investigated. Nb(C, N) particles measuring up to 10 nm are seen in austenite in
the final stage of rolling and after its conclusion prior to accelerated cooling of thick sheet. After intense accelerated
cooling, most of the niobium and vanadium is retained in the solid solution, as confirmed by the vigorous deposition of (Nb,
V)(C, N) particles measuring ∼2–4 nm in ferrite after tempering at 600°C. In coil production, the particles observed may be
the result of general deposition or interphase deposition, depending on the cooling of the strip on the output roller conveyer
of the continuous broad-strip mill. Carbonitride particles measuring 2–8 nm are deposited at winding temperatures of 550–570°C
in steel with niobium and vanadium and at 590°C in steel without vanadium. 相似文献
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包钢X60管线钢(%:0.04~0.06C,1.24~1.30Mn,0.04~0.05Nb,0.006~0.008Ti,0.015~0.030V)经6道次CSP(紧凑式带材生产技术)轧制后存在严重的混晶。通过不加V,成分改为(%):0.06~0.08C,1.24~1.30Mn,0.02~0.04Nb,0.007~0.010Ti,并第1、2道的压下量分别由≥39%和≥36%提高到≥42%和≥40%,为奥氏体再结晶的充分进行提供了温度和能量条件,消除混晶组织,钢的晶粒尺寸为5.6~8.0μm 相似文献
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采用Gleeble3500热模拟试验机,研究了含铌Q345钢奥氏体静态再结晶行为、铌的碳氮化物在奥氏体和铁素体中的析出行为等实验,铌在钢中的强化作用机理。根据上述结论,邯钢2250热轧厂生产了以碳、锰为主要成分,并加入微量铌元素,将原热轧带钢Q345的屈服强度由345 MPa提高到550M Pa。对生产的微铌处理550 M Pa钢的组织和力学性能作了检验,在细晶强化、沉淀强化和相变强化等复合强化的综合作用下,热轧带钢屈服强度均达到550 MPa以上,塑性良好。 相似文献
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Kelvin Y. Xie Lan Yao Chen Zhu Julie M. Cairney Chris R. Killmore Frank J. Barbaro James G. Williams Simon P. Ringer 《Metallurgical and Materials Transactions A》2011,42(8):2199-2206
The microstructure and corresponding tensile properties of both plain and Nb-microalloyed grades of ultrathin cast strip (UCS) low alloy steel produced using the CASTRIP® process were studied. Both as-cast and hot-rolled strip cast steels with various levels of Nb microalloying were manufactured and investigated in this study. Hot rolling had little effect on the yield strength of Nb microalloyed UCS specimens for a given chemical composition, but resulted in a slightly finer microstructure. The effect of Nb microalloying was significant, and this is attributable to the promotion of finer, tougher austenite transformation products such as bainite and acicular ferrite at the expense of large polygonal ferrite grains. A fine dispersion of Nb solute clusters was observed in all Nb-containing steels following hot rolling, and it is suggested that this also contributes to the observed strengthening. 相似文献