稀土元素在高强韧钢中的作用及应用前景

深入分析了稀土在钢中的作用机理,阐明了稀土是钢的一种有效的深度净化和变质剂,固溶稀土的存在强烈影响微结构,可控制局域弱化,降低微结构的能态,有效抑制钢中有害元素和脆性相偏聚所造成的脆性断裂,稀土可望成为发展21世纪高强韧钢,提高高强钢韧性的重要元素。     

宝钢高韧性管线钢的工业性生产

通过高韧性管线钢的研究和批量生产，宝钢已较好地掌握了高韧性管线钢的生产工艺和质量控制技术，化学成分和力学性能稳定，波动范围小。－３０℃的夏比冲击功大于９０Ｊ，屈服强度的波动值可控制在１００ＭＰａ范围之内，焊管焊接热影响区的冲击功能与管体母材相近。产品的质量达到日本进口板卷的实物水平。     

高强高韧钛合金研究与应用进展

航空航天业的发展对高强度、高断裂韧性的新型钛合金的需求越来越迫切,研究具有自主知识产权并用于航空大型结构件的新型高强高韧钛合金得到世界各国的重视.综合评述了国外传统的Ti-1023、BT22合金、β-21S合金、β-C合金,新型Timetal555和VST55531合金以及我国的TB2和TB10合金等7种高强高韧钛合金研究及应用现状,分析了合金的成分、组织、强度、塑性、断裂韧性等特点.根据国内外高强高韧钛合金发展现状,提出发展方向:研制Rm≥1300 MPa,K(IC)≥55 Pa·m(1/2)新型高强韧钛合金;新型合金成分应以Ti-Al-Mo-V-Cr系为主;探索加工工艺与高强高韧钛合金合金组织及性能的关系;发展具有优异的淬透性及良好的锻造性能为主的大型锻件用高强高韧钛合金.     

高强度管线钢的微观组织与冲击韧性

研究了具有不同微观组织类型的高强度管线钢的夏比冲击韧性.结果表明,针状铁素体型管线钢比多边形铁素体 少量珠光体型管线钢具有更高的冲击韧性.对于针状铁素体型管线钢,可通过减少夹杂物,获得均匀细小的铁素体晶粒、细小弥散的M/A岛和析出物,来获得优异的冲击韧性.     

Determination of Thermal and Mechanical Material Properties of Ultra‐High Strength Steels for Hot Stamping

Direct and indirect hot stamping presently constitutes one of the most innovative forming technologies in the automotive industry through the combination of forming and hardening in one process step or line. Thus, structural components with strength up to 1600 MPa can be accomplished with the quench hardenable ultra‐high strength steel 22MnB5. With respect to the numerical investigation of the feasibility of different parts the knowledge of various thermal and mechanical material characteristics determined under process relevant conditions are required. Within the scope of this paper different experimental methods will be introduced for the determination of material properties according to the typical time‐temperature characteristics of the hot stamping process, as well as the modelling of it as input data for the FE analysis.     

超高强度热冲压用钢中H的扩散与氢致滞后开裂行为

采用阴极充H、恒载荷拉伸和电化学H渗透等试验方法,研究了超高强度钢22MnB5Nb的H扩散行为及氢致滞后开裂性能,并与常用热冲压钢22MnB5进行了对比。结果表明,H在22MnB5Nb钢中的扩散系数为3.02×10-7 cm2/s,显著低于22MnB5钢;与22MnB5钢相比,22MnB5Nb钢具有较好的耐氢致滞后开裂性能;这是由于22MnB5Nb钢晶粒较细小,增加了晶界的有效面积,使H陷阱分布更均匀,进而抑制H向裂纹尖端扩展,避免了局部H的富集。     

不同加热温度下钒对车轮钢强韧性的影响

研究了不同正火加热温度下钒对车轮钢强韧性的影响.结果表明,当加热温度较低时,在强度与无V钢相同的情况下,加钒可显著提高车轮钢的低温冲击韧性;当加热温度较高时,在韧性与无V钢相同的情况下,加钒可显著提高车轮钢的强度.含V车轮钢存在一个适中的加热温度,可获得较好的强韧性匹配.含V车轮钢力学性能的变化规律与V(C,N)的溶解与析出行为有关.     

高强韧性双相钢的研究与开发应用前景

介绍了一种拳兴的具有高强声望生的钢一双相钢的国外外研究和应用状况，阐述了双相钢的显微组织特征、高韧塑性机理及综合机械性能的特点，提出了对我国加速开发、研制、生产双相钢的建议。     

硅、锰系TRIP钢成分及热处理工艺的优化

本文采用正交设计及方差分析法,对获取良好TRIP效应的Si、Mn系低碳低合金钢化学成分及热处理工艺进行了优化.结果表明:化学成分为0.28%C-1.62%Si-1.09%Mn的钢,经等温淬火工艺790℃×4min→400℃×3min处理后,获得最佳综合机械性能,强塑积达322.33MPa·%.     

不锈钢轧制中模型参数的优化

描述了不锈钢分公司1780mm热轧厂在不锈钢生产过程中产生的一系列与模型相关的问题,对模型重要设定控制参数进行了优化,总结了所取得效果和存在问题,为不锈钢正常生产提供了有力保证.     

1780mm热连轧粗轧宽展模型参数优化研究

1780mm热连轧生产线的粗轧宽展模型分析与其实际应用效果存在较大误差。为提高宽度控制预报精度，采用了优化宽展模型参数法来提高模型精度；运用麦夸尔特法（Levenberg-Marguardt）和优化程序回归出模型的参数。用优化后的参数替换原有模型参数来控制宽度。经检验，宽度预测精度与优化前相比有显著提高。     

影响连续镀锌模拟线生产高强双相钢微观组织和性能的因素

探讨如何改善镀锌或镀锌合金化钢板基层,比如在实现高强度的同时,保持高的整体成形性能(拉伸塑性)、局部成形性能(冲裁边部塑性)和良好的点焊性能。众所周知,双相钢的强度受几个因素控制,包括最终组织中的初生(未回火)马氏体量。然而,仍不完全清楚控制最终组织中马氏体量的因素,而确定这些因素是本研究项目的主要内容。最终组织中测定的新生马氏体量认为等于临界退火时形成的奥氏体量减去当钢在经历从临界退火温度(IAT)冷却至460℃、在460℃等温过程中、最终冷却至室温是转变成其他各种相变产物的奥氏体量以及在室温下保留的残余奥氏体量。最新研究发现,特定钢在临界退火过程中形成的奥氏体量受到退火温度、热轧带钢(卷取温度)和冷轧(冷压下量)等退火前条件的强烈影响。研究了退火前条件和4种退火工艺的组合,确定实现这些更高强度DP钢最佳的强度-成形性能匹配所需的最佳热处理路线。研究用钢包括(i)具有良好点焊性能的低碳钢,(ii)加入Mo提高淬透性和Cr提高强度,(iii)加入V实现细晶、析出强化和抗回火软化。当所采用的工艺适当,这些钢具有良好的综合性能,抗拉强度高达1 000 MPa、总伸长率达到25%,面缩率45%,扩孔率达到50%。给出并讨论了这些研究成果。     

露天矿爆破参数优化试验研究

就兰尖铁矿原爆破效果存在的问题，提出并进行爆破参数优化试验。实施优化后的爆破参数、装药结构及其它改进措施，取得了满意的爆破效果和良好的技术、经济、安全效益。     

High‐Strength Steels in Welded State for Light‐Weight Constructions under High and Variable Stress Peaks

In design codes (Eurocode, British Standard and others) for the dimensioning of welded joints, no distinction is made between low, medium and high strength steels. Because of a lack of general knowledge about the benefits of high‐strength steels and also because of missing information in design codes, in many cases design engineers still use low or medium strength steels (R_p0.2 < 400 MPa) and compensate for high loads under constant or variable amplitude loading or overloads by increasing dimensions. Given this situation, it was deemed necessary to establish criteria for the design of light‐weight welded constructions under high and variable stress peaks using new classes of high strength steels, such as S355N (normalized), S355M (thermomechanically treated), S690Q (water quenched) and S960Q (water quenched), and to perform more reliable evaluations of the fatigue performance of high strength steel structures subjected to complex loading with regard to light‐weight design and economics. For the comparison of the fatigue strengths of the investigated steels the notch factors present were taken into account. Additionally, the real damage sums were determined in order to give recommendations for the fatigue life estimation. Under constant amplitude loading, no significant difference in the bearable local stress amplitudes for the butt welds can be detected for the four investigated steels. Under variable amplitude loading, the butt welded (lower notch factor) high strength steel S960Q has advantages in the case of the normal Gaussian spectrum and in the case of overloads, especially under pulsating loading. For the transverse stiffeners (high notch factor), slight advantages for the high strength steel S960Q exist, only in the case of pulsating overloads. However, the advantages of high strength steels in case of static loading are indisputable. In most of the investigated cases, overloads lead to a benefit in fatigue life.     

Effects of Coiling Temperature on Strength,Yield Ratio and Precipitation Behaviors of Hot Rolled High Strength Microalloyed Steel for Cold Forming

Various hot rolling schedules were applied to a Nb,V,Ti contained HSLA steel.Coiling temperature had crucial effects on not only yield strength,but also yield ratio and precipitation behavior.600Mpa yield strength is achieved when coiled at 450℃,which is 100Mpa higher than those coiled at 570℃.However,the low coiling temperature had adverse effect to increase yield ratio,which increased from 0.78 to 0.88 as coiling temperature dropped from 570℃ to 450℃.High resolution SEM analysis shows that sizes of Nb,V,Ti precipitates are affected by coiling temperature.Coarse (Nb,Ti)(C,N) precipitates up to 5μm are observed at higher coiling temperature and to decrease tensile strength,where high coiling temperature corresponds to low cooling rate.With strong cooling and coiling capacity of Shasteel’s 1450mm width hot rolling mill,these results indicate that strength and formability of the steel can be balanced when coiling temperature has been optimized.Alloying and microalloying costs can be reduced by efficiently utilizing the capacity of rolling mill.Alumina inclusions are found to act as nucleus for Nb,V,Ti precipitates,contributing to coarsening of precipitates.     

先进高强度汽车用钢的多维度协同设计与调控

阐述了先进高强度汽车用钢的概念,介绍了其发展及应用情况。提出了汽车用钢多维度设计理念,包括热处理过程中的多尺度设计和具有良好成形性的汽车用钢设计。指出汽车轻量化设计不应仅局限于获得理想的力学性能,要进行多维度的协同设计,并通过智能化微观组织调控来定制及满足差异化的要求。     

V微合金化对高强高耐候乙字钢性能的影响

以中频感应炉冶炼不同钒、氮含量试验钢为材料,通过力学性能检验和析出相分析,研究了钒微合金化对高强高耐候乙字钢性能的影响。结果表明:钒在高强高耐候乙字钢中能起到细晶强化或沉淀强化的作用,而氮的加入可促使钒从固溶态向析出态转化,增大钒的析出强化作用。终轧温度对钒氮的析出强化作用敏感,终轧温度越低,V(C,N)的析出量越大,屈服强度越高,但强塑性匹配最好的终轧温度在850℃左右。     

高强钢先进成型技术和本构模型研究现状与发展趋势

高强钢是汽车车身轻量化的首选材料,但其成型问题一直是限制其推广应用的重要因素。对高强钢的先进成型技术,如液压成型、激光拼焊、热冲压成型等的原理、特点及最新研究进展进行了论述。同时,对先进高强钢的本构模型进行了阐述,以期对改进高强钢成型性能提供依据。     

高炉原燃料显热利用能效优化技术解析

通过对高炉铁前原燃料生产过程的能效利用进行计算分析,炼铁消耗铁前的原燃料其显热资源有40kgce/tFe以上未被利用,节能潜力巨大,结合分析结果提出了原燃料热装的技术方案,该方案能降低高炉工序能耗约9%以上,同时对热装方案所带来的一系列问题进行了分析和讨论,指出该方案的实施能有效的解决当前原燃料显热利用水平低,高炉炼铁工序能耗高的问题,有较好的发展前景。