硫含量和夹杂物控制对冷轧马氏体钢板冷弯性能的影响

冷轧马氏体钢主要用于汽车安全件,成形以冷弯或辊压为主,因此,马氏体钢的冷弯性能至关重要。以宝钢工业产线轧制的980 MPa级冷轧马氏体钢为研究对象,研究了不同S含量水平和Ca处理对冷轧马氏体钢弯曲性能的影响,分析了不同S含量水平下钢中的夹杂物数量和级别。通过控制S含量和采用Ca处理,可以明显降低马氏体钢中的夹杂物数量、尺寸,最终明显提高冷弯性能。宝钢开发的980 MPa级冷轧马氏体钢已经成功应用于乘用车安全部件的制造。     

1500MPa级冷轧马氏体钢板的弯曲性能和韧性研究

冷轧马氏体钢板以其高强度特点,在汽车结构件制造中具有较大的减重潜力,逐步得到越来越多的应用。马氏体钢板延伸率较低,随着钢板强度提高,塑性进一步下降,能否满足汽车零部件制造对成形性和安全保护的要求,值得关注。以1 500 MPa级别的冷轧马氏体钢为研究对象,测试了其90°弯曲性能和在不同温度的韧性及断裂方式,并根据试验结果对1 500 MPa级马氏体钢板应用的条件进行了分析,希望能够对该类型的超高强钢板在汽车制造方面的应用有一定的提示作用。     

冷轧980 MPa级马氏体钢产品研发

文章根据冷轧980 MPa级马氏体钢技术要求进行了化学成分和生产工艺设计,并采用中试平台开展了冷轧980 MPa级马氏体钢实验室退火工艺研究。研究结果表明,采用相同化学成分及轧制工艺生产的冷轧980 MPa级马氏体钢通过调整退火缓冷温度得到的产品屈服强度为750～940 MPa,抗拉强度达到1 020 MPa以上,延伸率在10%以上,满足技术要求。明确了缓冷温度对冷轧980 MPa级马氏体钢组织性能的影响规律,结合显微组织及成品机械性能确定该成分体系下均热温度为800℃、缓冷冷速为3℃/s、快冷冷速为45℃/s、快冷温度为280℃时,最佳缓冷温度为680℃。     

河钢集团汽车板产品研发与技术创新

 为了应对汽车行业对安全性、轻量化及节能环保的要求,河钢集团构建了汽车板生产、研发与EVI的创新体系,在此基础上实现了超深冲、高强钢系列品种的全覆盖,运用轻量化材料技术实现抗拉强度980 MPa 级的DP钢、780 MPa级的TRIP钢、1 500 MPa级的马氏体钢和热成形钢的批量供货,创新并实现了1 180 MPa级的DP钢、镀层热成形钢以及Q&P钢生产工艺。此外,介绍了河钢集团典型的轻量化钢种DP钢、马氏体钢、镀层热成形钢、Q&P钢的产品技术特点,指出汽车板材料轻量化和提升应用技术服务等是今后河钢集团汽车板产品结构调整与技术创新的发展方向。     

成型性和焊接性优良的超高抗拉强度钢的开发

概述了JFE开发并商业化生产成形性和焊接性均优良的780—1470MPa超高强度系列冷轧钢板。该系列钢板可实现汽车减重,提高碰撞安全性能。该系列钢板是JFE采用自主开发的WQ—CAL（水淬-连续退火生产线）工艺生产的,采用该工艺可以大幅降低钢中合金元素的添加量。其中新开发的1180MPa级抗拉强度钢板的伸长率得到大幅提高,是传统相同级别钢板的1．5倍,与980MPa级钢相同,且其拉伸凸缘性也与980MPa级钢相当。另外,1180MPa级钢的加工淬透性和烘烤硬化性也十分优良,完全可以替代热冲压部件。新开发系列钢可用于白车身结构件,如中梁（加强件）、保险杠、座椅结构架、座椅横挡及座椅部件（如机械锁扣）等多种用途。     

JFE制钢公司开发出提高点焊接性的780MPa和980MPa级高强度钢板

JFE制钢公司开发了抗拉强度为780MPa和980MPa级高强度冷轧钢板和合金化热镀锌钢板,它不仅可用作汽车高强度构件和冲撞吸收构件,而且可以提高点焊接部的可靠性。     

宝钢开发出为汽车“减重节能”的热镀锌TRIP钢

日前，宝钢成功开发出热镀锌TRIP钢板。热镀锌TRIP钢又称为热镀锌相变诱发塑性钢，兼有高强度和高延伸率，是应对汽车“减重节能”所用高强度钢板中的一种。自2002年宝钢实现600兆帕级别冷轧TRIP钢的产业化后，研究院汽车用钢研究所克服了诸多困难，在国内率先成功试制出强度级别为600兆帕的热镀锌TRIP钢，产品实物性能达到国际同类产品水平。     

980MPa级冷轧双相钢连退断带原因分析及改进措施

分析了980 MPa级别冷轧双相钢在连退线入口非焊缝处断带的产生原因,结果显示,热轧显微组织为铁素体-马氏体两相组织,且两相分布均匀,钢板通宽方向上硬度分布均匀.冷硬钢板组织为典型的纤维状两相组织,且宽度方向上硬度分布也比较均匀.断口呈撕裂状,且存在较多的韧窝,为典型的韧性断裂.断口附近存在较多大小不一的裂口,且钢板板...     

700MPa级大梁钢W撑开裂原因分析

高强度低合金钢板产品的质量稳定一直是汽车用户和钢铁企业追求的目标,特别是屈服强度为700 MPa级的高强汽车大梁钢板.本文利用光镜、电镜和EBSD观察分析了不同成分的700 MPa级大梁钢W撑的显微组织、晶粒尺寸、晶界取向和钢中析出相.结果表明,铌钛微合金化强化的700 MPa级大梁钢较单钛强化的大梁钢晶粒细小均匀,折...     

宝钢试制成功世界最高强度的汽车用冷轧马氏体钢

<正>2015年10月,1700MS钢(马氏体钢,抗拉强度为1 700 MPa)在宝钢试制成功,标志着宝钢在汽车高强钢研发与生产上的又一个新突破,预计2016年可提供用户试用。1700MS钢是目前世界上抗拉强度最高的汽车高强钢钢种,主要用于保险杠、车门防撞杆等零件,用于前后保险杠时可大大改善防撞性能和减重。在保证碰撞安全的前提下,1700MS钢较之前的高强     

转炉炉壳热应力分析

根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。     

Results of treatment of cancer of the cardia

Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.     

焦炭热性能指标意义浅析

通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。     

Effect of antibiotics of chemotaxis of human leukocytes

The effect of 20 different antibiotics on chemotaxis by human neutrophils was studied. Human leukocytes incubated with chloramphenicol, rifampin, sodium fusidate, and tetracyclines in vitro showed markedly depressed migration. The mechanisms by which these antibiotics affect leukotaxis are discussed.     

Quality of life of relatives of mental patients

Usage of quality of life of psychiatric patients' relatives as the parameter of estimation of the quality of psychiatric care is considered. By means of standard questionnaire elaborated by the authors as well as by means of both individual and group conversations the quality of life was analyzed in 40 relatives which lived together with psychiatric patients. Different spheres of their life and difficulties (financial, social-psychologic, production) were examined in families with such patients. The defects of psychiatric care that had direct influence on the quality of life of the psychiatric patients' relatives are outlined.     

The effect of amount of possession of the trait of hostility on accuracy of perception of hostility in others.

Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)