低碳含铌钢表面裂纹的研究与改进措施

 主要研究了低碳含铌钢的表面裂纹形成的原因。通过对表面裂纹缺陷部位进行金相组织观察、SEM(EDS)、金属原位分析,得知低碳含铌钢表面裂纹附近存在夹杂物,铌元素的含量富集。钢水中的氮过高、连铸二冷水强度是影响铌提前凝固析出富集的主要原因。通过降低钢水的氮含量,适当提高热矫温度等工艺的优化措施,明显降低了低碳含铌钢的表面裂纹。     

高强IF钢合金化工艺应用分析

主要介绍了安钢生产高强IF钢的工艺控制情况,分析了不同合金化方式对合金元素收得率、钢中氧含量、RH脱碳、后期合金增碳以及钢水洁净度控制的影响。认为LF配加锰铁和RH脱氧后配加金属锰两种方式对高强IF钢中碳含量和钢水洁净度的影响相差不大,均能够满足产品需求。     

12Cr1MoV钢轧材表面裂纹控制技术的研究与应用

针对12Cr1MoV钢在生产过程中出现不同程度的表面裂纹,采用金相显微镜以及扫描电镜检测确认,轧材裂纹是由铸坯裂纹导致。对裂纹的形成原因进行了分析,得出钢水洁净度,钢水氮含量以及结晶器保护渣是导致铸坯裂纹的主要原因,通过控制电弧炉终点碳、优化精炼渣系以及钙化处理脱氧产物提升钢水洁净度,控制圆坯表面氮化物析出,保证钢中N含量0.007%,同时使用管坯钢保护渣,使得12Cr1MoV钢表面裂纹缺陷率由1.6%下降到0.3%。     

510L汽车大梁钢表面纵裂纹控制

汽车大梁钢510L由于碳含量在包晶区内,容易出现表面纵裂,本文通过控制钢中碳含量、钢水过热度,使用专用结晶器保护渣,调整结晶器冷却水流量等一系列措施,表面纵裂纹明显减少。     

12CrlMoV钢轧材表面裂纹控制技术的研究与应用

针对12Cr1MoV钢在生产过程中出现不同程度的表面裂纹,采用金相显微镜以及扫描电镜检测确认,轧材裂纹是由铸坯裂纹导致。对裂纹的形成原因进行了分析,得出钢水洁净度,钢水氮含量以及结晶器保护渣是导致铸坯裂纹的主要原因,通过控制电弧炉终点碳、优化精炼渣系以及钙化处理脱氧产物提升钢水洁净度,控制圆坯表面氮化物析出,保证钢中N含量 < 0.007%,同时使用管坯钢保护渣,使得12Cr1MoV钢表面裂纹缺陷率由1.6%下降到0.3%。     

中厚板表面裂纹控制

针对中厚板表面经常出现裂纹缺陷的问题,通过材料显微组织分析、坯料跟踪和对比生产实验,发现中厚板表面裂纹源于板坯裂纹。采取调整钢水成分,优化连铸工艺,提高入炉板坯表面质量等措施,减少了钢板裂纹不合格品,产品合格率提高了4．43％,提高了中厚板质量。     

减少宽厚板坯表面纵裂纹的改进实践

分析了钢水碳含量、硫含量、钢水纯净度、拉速变化、浸入式水口参数及结晶器液位波动等对铸坯表面纵裂纹的影响,不合理的化学成分、拉速变化及结晶器液面波动大等是导致纵裂的主要原因。通过相应采取优化钢水成分、优化浸入式水口参数、采用钢包下渣检测技术和结晶器液位控制系统改造等措施,使板坯表面裂纹率由0．76％降到了0．18％以下。     

炼钢生产过程中增氮分析与控制

控制钢种氮含量,对提高铸坯质量很关键。中厚板卷厂炼钢过程各环节钢水氮含量检测统计显示,连铸机浇注过程是钢水增氮的主要环节,而且氮含量高的炉次铸坯的横裂纹、碎裂纹检出率较高。通过分析钢液中氮的行为,加强连铸保护浇铸的控制手段,将终点氮含量控制在50 ppm以内。     

含硼钢板坯表面纵裂原因分析及控制措施

含硼钢是目前应用比较广泛的一种钢种,其优点是增加钢的淬透性,提高钢材的高温强度,从而节约其他合金,但是含硼钢板坯易产生表面纵裂纹,为控制含硼钢板坯表面纵裂纹的产生,从钢水脱氧工艺、钢中硼含量、连铸工艺等方面进行了研究,找出了板坯表面纵裂纹的影响因素,通过采取相应的工艺措施,降低了含硼钢板坯表面纵裂纹比率。     

45#金属表面带状裂纹成因分析及措施

通过裂纹形貌,裂纹截面轮廓、连铸低倍观察及成分含量分析等方法,对45#钢表面带状裂纹进行分析,结果表面:钢水气体含量偏高形成的皮下气泡、C、P偏析形成的偏析带及连铸低倍存在微裂纹及夹杂是产生表面带状裂纹的主要原因。     

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.