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加速腐蚀环境下高强耐候钢Q450NQR1的耐蚀性能研究 总被引:5,自引:0,他引:5
Q450NQR1是以Cu,Cr,Ni合金化为主的屈服强度达450 MPa以上的高强耐候钢,其耐大气腐蚀性能是决定使用性能的重要指标之一.通常利用加速腐蚀试验采用失重法表征耐候钢的耐大气腐蚀性能.通过周期浸润模拟加速腐蚀试验,对比研究了高强耐大气腐蚀钢Q450NQR1和普碳钢Q345qD的加速腐蚀性能,并用XRD对锈层的相组成进行了分析.结果表明:在试验条件下,Q450NQR1的腐蚀失重量和失重速率明显低于普通碳钢Q345qD.Q450NQR1表面锈层主要由保护性较好的α-FeOOH相组成,该锈层为基体提供了良好而稳定的保护作用. 相似文献
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汽车用耐大气腐蚀钢的试验研究 总被引:1,自引:0,他引:1
本文介绍了汽车用耐大气腐蚀钢的钢系选择与试验研究,以解决载重汽车车箱的腐蚀问题。通过对试验的成分筛选和性能试验,得出了汽车用耐大气腐蚀钢应含有稀土、并避免钛的结果、钢号以 Cu—P—Re系钢的06Cu P Re 和09Cu P Re 为宜。这是一种经济性冷成形用耐大气腐蚀钢。 相似文献
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介绍了08CuPVRE耐大气腐蚀用钢冶炼生产试验情况,阐述了稀土加入方法的选择及提高稀土回收率、改善钢水流动性的有效措施。 相似文献
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采用真空感应炉、热模拟试验机、ICP发射光谱仪、光学显微镜、TEM和电子拉伸试验机等设备,研究了V-Ti-N耐大气腐蚀钢(0%V、0.05%V、0.10%V和0.15%V)的动态CCT曲线、析出钒、晶粒尺寸和强度。结果表明:在耐大气腐蚀钢中添加0.10%V,对CCT曲线的影响有限,贝氏体转变温度都低于600℃;V-Ti-N耐大气腐蚀钢的晶粒尺寸为6.2~7.8μm,产生了101~175 MPa的沉淀强化,屈服强度随着钒氮积的增加而升高,但强化效率逐渐降低;V-Ti-N微合金化较适合于生产400 MPa和450 MPa级高强度耐大气腐蚀钢,此时,钒含量应小于0.10%。 相似文献
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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。 相似文献
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K Ohta M Nishi M Ueda S Ohyama T Matsubara T Takahashi T Nakajima 《Canadian Metallurgical Quarterly》1998,99(9):589-594
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. 相似文献
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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) 相似文献
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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. 相似文献
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TA Solokhina LS Shevchenko IuV Se?ku EG Rytik LV Besedina TS Veshchugina 《Canadian Metallurgical Quarterly》1998,98(6):42-46
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. 相似文献
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