热轧板带钢冷却过程中热力耦合计算及变形分析

采用有限元分析工具ANSYS，利用不同的表面传热系数，进行了热轧板带钢在常规强制对流层流冷却(冷却速度在30℃／s左右)以及超快速冷却(UFC，短时冷却速度可达300℃／s以上)情况下的热力耦合分析，计算出带钢在不同冷却强度下温度与应力的二维分布，在此基础上进行了残余应力及由此引起变形的理论分析。通过比较分析的结果，初步得出UFC的适用范围。     

包钢CSP生产线生产540 MPa级热轧双相钢

介绍了在包钢CSP生产线研制540 MPa级热轧双相钢的工业化生产试验.采用C-Mn钢为原料,分别利用原层流冷却能力和超快冷设备,通过控制轧制和控制冷却工艺,成功开发出540 MPa级热轧双相钢160 t.试制的钢带具有屈服强度低、屈强比小、伸长率大、n值高及低温冲击韧性良好等特点,并具有拉伸曲线无屈服平台、马氏体呈岛状均匀分布在铁素体晶界上等典型双相钢的特征.经汽车制造厂试用,制成了汽车横梁和重型翻斗车护板等构件.     

改善GCr15轴承钢酸蚀低倍质量的生产实践

针对济源钢铁GCr15轴承钢棒材横截面酸蚀孔洞较严重的问题,分析酸蚀孔洞的成因.分析表明,贫铬区域抗酸蚀能力弱,优先形成孔洞,而成分偏析和网状碳化物的析出是造成铬元素分布不均的主要原因.为此,在实际生产中延长开坯加热时间和投用超快冷设备,最终酸蚀孔洞缺陷得到明显改善.     

新一代TMCP技术的发展

以自主研发的冷却速率可调（空冷至超快速冷却无级调整）、冷却温度精确控制的先进冷却技术和装备为 手段,对占钢材总量95%以上的热轧钢材,根据不同钢材成分、性能要求和相变规律设计相应的冷却路径和冷却过 程控制参数,进行钢材热轧和冷却过程中的微观组织有效调控,实现细晶强化、纳米析出强化、相变组织强化等各 种强化机制的综合强化,充分挖掘钢材的潜力。开发的工艺技术、冷却装备目前在热连轧、中厚板、H型钢、棒材等 生产过程中转化应用,开发出系列的减量化钢材产品。与传统的控制轧制和控制冷却技术相比,节省钢材合金用 量30%以上,或提高钢材强度100～200 MPa以上,大幅度提高冲击韧性,节约钢材使用量5%～10%,节能10%～ 15%。在上述工作的基础上,该技术已经列入《产业关键、共性技术发展指南（2011年）》《钢铁工业“十二五”发展规 划》和《产业结构调整指导目录（2011年本）》等国家文件。     

热轧带钢控制冷却新技术-UFC

对热连轧带钢生产线上超快速冷却（UFC, ultra fast cooling）技术的发展过程、冷却原理、设备组成、布置形式、应用实例做系统介绍。     

Thermal degradation of urea‐formaldehyde cellulose composites filled with aluminum particles: Kinetic approach to mechanisms

This article reports a study on structural characterization and thermal degradation kinetics of insulating/conducting urea‐formaldehyde cellulose (UFC) composites filled with aluminum particles. Structural characterization of UFC/Al composites carried out by SEM, XRD, and FTIR analyses reveals that composites are fairly homogenous, and the interactions between UFC and aluminum in UFC/Al composites are more probably physical in nature. Measurements of inherent thermal stabilities, probing reaction complexity, and thermal degradation kinetics of UFC and UFC/Al composites have been undertaken by thermogravimetric (TG)/differential thermogravimetric (DTG) analyses under nonisothermal conditions. The integral procedure decompositions temperature (IPDT) elucidates significant thermal stability of UFC, and higher aluminum contents in composites are capable of enhancing the thermal stability of UFC resin. TG/DTG analyses suggest highly complicated thermal degradation profiles of UFC and UFC/Al composites, which consist of various parallel/consecutive reactions. Generalized linear integral isoconversional method has been employed to determine the activation energies of thermal degradation processes. Substantial variations in activation energies of UFC and UFC/Al composites with the advancement of reaction verify their multi‐step reaction pathways. Advanced reaction model determination methodology with the help of a novel kinetic function F(α,T) reveals that the multi‐step thermal degradation of UFC goes to completion by principally following intricate nucleation/growth mechanisms. It is also found that aluminum more likely participates in the thermal degradation of resin and tends to alter its reaction mechanism. Detailed interpretations of the obtained kinetic parameters are given, and their probable physical significances are discussed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44826.     

Overexpression of UBA5 in Cells Mimics the Phenotype of Cells Lacking UBA5

Ufmylation is a posttranslational modification in which the modifier UFM1 is attached to target proteins. This conjugation requires the concerted work of three enzymes named UBA5, UFC1, and UFL1. Initially, UBA5 activates UFM1 in a process that ends with UFM1 attached to UBA5’s active site Cys. Then, in a trans-thiolation reaction, UFM1 is transferred from UBA5 to UFC1, forming a thioester bond with the latter. Finally, with the help of UFL1, UFM1 is transferred to the final destination—a lysine residue on a target protein. Therefore, not surprisingly, deletion of one of these enzymes abrogates the conjugation process. However, how overexpression of these enzymes affects this process is not yet clear. Here we found, unexpectedly, that overexpression of UBA5, but not UFC1, damages the ability of cells to migrate, in a similar way to cells lacking UBA5 or UFC1. At the mechanistic level, we found that overexpression of UBA5 reverses the trans-thiolation reaction, thereby leading to a back transfer of UFM1 from UFC1 to UBA5. This, as seen in cells lacking UBA5, reduces the level of charged UFC1 and therefore harms the conjugation process. In contrast, co-expression of UBA5 with UFM1 abolishes this effect, suggesting that the reverse transfer of UFM1 from UFC1 to UBA5 depends on the level of free UFM1. Overall, our results propose that the cellular expression level of the UFM1 conjugation enzymes has to be tightly regulated to ensure the proper directionality of UFM1 transfer.     

西气东输三线用X80管线钢板的研制

首钢集团秦皇岛首秦金属材料有限公司(首秦公司)在X80管线钢大批量稳定生产的基础上,针对西气东输三线项目用厚壁、大板宽X80管线钢技术要求和首秦炼钢与轧钢的技术装备条件,在TMCP工艺基础上通过采用优化的控冷工艺(联合使用UFC超快冷和ACC层流冷却),降低了合金成本,获得均匀稳定的力学性能。通过对首秦西气东输三线项目5.2万t X80管线钢的成分、工艺、组织、性能进行论述及统计分析,说明采用TMCP和优化的冷却工艺(OCP)生产的X80管线钢完全满足西气东输三线对大壁厚X80管线钢热轧钢板的技术要求,并且实现了良好的成本控制。     

超快速冷却技术在热轧带钢生产中的应用

介绍了超快速冷却技术在热轧带钢生产中的应用,包括超快速冷却系统的布置,热轧生产线的改造,超快速冷却的过程控制和超快速冷却的数学模型等。热轧带钢采用超快速冷却代替层流冷却可提高其性能。     

Effects of Technological Parameters on Microstructures and Properties of Low Cost Hot Rolled Dual-Phase Steel on CSP Line

The effects of technological parameters on microstructures and properties of low cost hot rolled dual-phase steel was researched by design different finish rolling temperature,mid cooling temperature between laminar cooling and UFC (ultra fast cooling) and stable UFC rate on the same gauge strips with the same chemistry composition during the manufacture process.It is the key for controlling coil temperature to control finish rolling temperature and mid cooling temperature between laminar cooling and UFC that based on stable UFC rate precondition.The lower finish rolling temperature,with mid cooling temperature between laminar cooling and UFC,the better to form martensite is.The foundation of developing the similar productions on the similar product line was supplied.It is good to technological advancement of developing high affixation value production as hot rolled DP steel,TRIP steel etc.in CSP line.