稀土对B级船板钢冲击韧性的影响

利用扫描电镜(SEM)和能谱仪(EDS),研究了不同稀土含量对B级船板钢热轧板断口形貌及对钢中夹杂物形成的影响。研究发现,在B级船板钢中加入稀土后,稀土元素La、Ce能够与钢中的As相互作用形成复合相;稀土在钢中起到变质夹杂物的作用,从而提高了钢的低温冲击韧性;在本实验中,稀土的最佳含量为0.019%。     

高强度船板钢裂纹的原因分析

由于经济的快速发展和进步,带动各行各业的不断扩大和经济效益的提高,造船业随着旅游运输和工业生产的发展而不断壮大。在造船业中,热轧板是使用非常广泛的基础核心材料,其中的高强度船板的使用数量逐年提升,主要是用在船的主体结构上。但是,高强度船板钢裂纹不断出现,导致船板的质量出现问题,直接影响船的制造和使用。本文将对高强度船板钢裂纹产生的原因进行分析和讨论,找到问题所在为,高强度船板的生产制造提供参考。     

宝钢集团-钢不锈钢工程工艺概述及精品策略浅析

宝钢集团第一阶段性战略目标为2005年建成国内最大的精品钢材生产基地。一钢不锈钢热轧板卷工程是建设不锈钢精品基地的核心工程，经过国务院批准建设的一钢《不锈钢及碳钢热轧板卷技术改造项目》由不锈钢和碳钢热轧板卷两大独立生产体系组成。项目的立项经过了多项专题     

SPHC钢热轧板卷破边成因及防治措施

针对安钢热连轧SPHC钢在轧后出现的严重破边现象,对热轧板卷破边的成因及防治措施进行了研究.从机制认识出发,结合金相检验、扫描电镜分析、成分分析等方法,对破边缺陷的特征及成因进行了分析.结果表明,热轧板卷破边可能与板坯角部表观质量没有直接关联,钢中Mn/S比偏低及加热温度偏高也将导致热轧板卷破边缺陷严重.据此,从生产工...     

热轧卷取机卸卷困难故障分析及排除

针对热轧板卷取机卸卷故障,分析了热轧板卷取机结构原理和故障产生原因。对卷取机卸卷小车液压控制回路进行改进,解决了卸卷困难的问题,提高了轧制节奏和钢卷外观质量,保证了生产的稳定顺行。     

CSP热轧板卷边部裂纹成因及控制

为了抑制CSP热轧板卷边部裂纹,对CSP热轧板卷边部裂纹的成因进行了研究.CSP热轧板卷边部裂纹缺陷主要有3类:边部横裂纹、边部纵裂纹、边部烂边或掉块等.板卷产生边部裂纹的主要原因是:连铸坯表面边部横裂纹(包括深的振痕)和边部的细小纵裂纹,在加热和轧制过程中不断扩展;钢液在凝固以及铸坯在冷却、均热、轧制、层流冷却和卷取等过程中的热应力、机械应力以及相变应力等作用力超过钢的塑性变形抗力.抑制CSP热轧板卷产生边部裂纹的主要措施是:控制好合适的钢水成分;制定有效的工艺参数,如结晶器热流密度、结晶器振动参数、二冷冷却强度等.工业试验结果表明,CSP热轧板卷边部裂纹率由7.93%降低到1.81%.     

炉卷机组36mm高强度船板AH36的研制工艺

介绍了安钢炉卷机组开发高强度船板AH36的主要工艺。采用Nb微合金化成分设计,铁水预处理及炼钢连铸新工艺生产的高强度船板钢AH36综合力学性能良好,满足各国船级社认证要求。     

稀土对船板钢组织及低温韧性的影响

测定了稀土对船板的低温韧性的影响,并通过观察不同稀土含量时钢的组织及夹杂物的形貌,研究了稀土对船板钢热轧板断口形貌及对钢中夹杂物形成的影响。研究发现,加入稀土后,钢中的铁素体含量有所增加,而对其晶粒度没有明显的影响;而加入适量的稀土后(RE:0.018%~0.027%),常温下的冲击韧性下降,但在低温情况下的冲击功高于未加稀土的钢样,此时主要存在的稀土夹杂相是:RE-O-S-Ca和RE-S-Ca,而稀土元素与As形成的复合相主要出现在稀土含量较高的样品中,而当钢中稀土含量过高时会形成数量较多、颗粒较大的以氧、硫为核心的稀土、砷复合夹杂,反而会恶化钢的冲击性能。     

本钢厚规格X70管线钢热轧板卷的生产试验

介绍了厚规格X70管线钢热轧板卷的成分设计与生产试验情况。对2种不同成分设计的碳加铬加钼和钢的精轧控制、轧制温度以及碳、铬、钼含量对热轧板卷强度和DWTT撕裂面积等性能的影响进行了对比分析,结果表明:用铬合金化,降低钼含量和控制适量的碳含量生产的厚度20.6mm热轧板卷,具有优良强度和韧性,综合性能指标达到API X70标准要求。     

船板钢的成分性能要求及研究现状

船板钢作为船舶制造和海洋工程的核心材料之一,其性能与质量直接影响着海洋工业的可靠性和安全性。综述了特殊服役条件下对船板钢化学成分以及性能的要求,介绍了船板钢的开发特点以及国内外生产船板钢的关键技术,分析了船板钢未来的发展方向,旨在为钢铁企业船板钢的开发提供借鉴。     

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。     

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。     

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.     

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)     

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.