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1.
以羰基铁粉和羰基镍粉为原料粉末,采用金属注射成形(MIM)工艺制备Fe-50%Ni软磁合金,分别采用炉冷、空冷、油冷和液氮冷等4种冷却方式对该合金进行热处理,借助TEM分析和居里温度测量等检测技术系统研究冷却方式对其磁性能的影响,并对不同热处理方式导致试样磁性能差异的根本原因进行分析。结果表明:热处理冷却方式对注射成形Fe-50%Ni软磁合金的密度、杂质含量和晶粒尺寸影响都不大,但对磁性能的影响非常明显,随冷却速率加快,该合金的矫顽力先增大后减小。液氮冷却的试样磁性能最好,其饱和磁感应强度为1.45T,矫顽力为7 A/m,最大磁导率为72.47 mH/m,初始磁导率为10.12 mH/m。油冷和液氮冷却试样中存在亚稳FeNi有序相,导致合金的磁性能大幅提高。  相似文献   

2.
以羰基铁粉和羰基镍粉为原料,采用金属注射成形(Metal injection molding,MIM)工艺制备Fe-50%Ni(质量分数)软磁合金,研究烧结气氛、烧结温度和时间以及热处理制度对其磁性能的影响。通过对不同工艺条件下试样的杂质含量、密度、金相和磁性能的分析,发现C、O等间隙杂质原子含量和热处理的冷却方式强烈地影响MIM Fe-50%Ni合金的最大磁导率和矫顽力,而相对密度是影响MIM Fe-50%Ni的饱和磁感应强度和初始磁导率的主要因素。试样经1 380℃氢气烧结3 h、650℃保温1 h再油淬,可获得最佳磁性能:饱和磁感应强度为1.496 T,矫顽力为4.8 A/m,最大磁导率为75.2 mH/m,初始磁导率为9.18 mH/m。  相似文献   

3.
注射成形Fe-50%Ni软磁合金的研究   总被引:3,自引:0,他引:3  
Fe-50 %Ni合金是一种典型的高磁导率和低矫顽力的软磁材料,有着广阔的应用前景.本次实验采用注射成形方法制取Fe-50 %Ni,研究了在注射成形工艺中烧结工艺对最终产品性能及微观组织的影响,并分析了影响产品磁性能的一些主要因素.实验表明,烧结温度的提高和烧结时间的延长能够较好改善产品的力学性能;密度是影响产品磁性能的主要因素,杂质(主要指(C、O、N)的含量和晶粒尺寸对剩磁、磁导率和矫顽力也有较大的影响;通过注射成形方法制取的Fe-50 %Ni,其性能要优于采用传统粉末冶金方法制造的Fe-50 %Ni.  相似文献   

4.
研究了Fe-17.5TCr-0.5%C及Fe-17.5%Cr-0.5%C-Z%Ni(Z=1-2.4)合金的组织和磁性。在低于A3温度退火后Fe-17.5%Cr.0.5%C合金由铁磁性的α相和M23C6相组成,合金具有高的比磁导率,好的软磁性。另-方面,当合金固溶处理后,导致有低的比磁导率的顺磁性的叮相组成。合金的比磁导率随温度降低而增加,这是由于γ相转变成磁性的α′相。在Fe-17.5Cr-0.5C合金中添加Ni降低了转变温度Ms,使顺磁性的γ相稳定化。退火Fe-17.5%Cr-0.5C%-Z%Ni合金也会导致形成铁磁性α相和M23C6相,具有软磁性,但这种软磁性稍低于Fe-17.5Cr-0.5C合金,主要是因为Fe—17.5Cr-0.5C—ZNi合金的晶粒尺寸较小。业已发现Fe-17.5Cr-0.5C—ZNi合金的软磁性能很大程度上取决于合金的残余应力。对该合金进行适合退火后,其软磁性能优于商业用Fe-18%Cr-8%Ni合金。  相似文献   

5.
多元系铁基非晶合金的抗氧化性和软磁性能   总被引:2,自引:2,他引:0  
本文研究了在一般铁基非晶合金Fe-Si-B的基础上添加铬、镍等微量元素形成的多元系非晶合金,经在空气中热处理后的抗氧化性和软磁性能。实验结果表明,随着微量元素铬含量增加,非晶合金的抗氧性和软磁性能提高。  相似文献   

6.
非晶态软磁材料具有独特的结构和磁性能,从60年代至今,其从快冷非晶合金发展到现在的纳米晶软磁合金,对相关产业的发展和进步起到了巨大的作用。本文从非晶态物理的角度,综述了非晶态软磁材料的结构与磁性能的物理基础。  相似文献   

7.
烧结工艺对注射成形Fe-50%Ni软磁材料磁性能的影响   总被引:2,自引:1,他引:1  
采用单质羰基铁粉和羰基镍粉,运用注射成形工艺制得了高性能的Fe-50%Ni软磁材料,系统地研究了烧结工艺中不同的烧结温度、烧结时间对材料的密度、磁性能的影响,同时对采用本工艺方法制得的Fe-50%Ni软磁材料的磁化曲线和磁滞回线进行了测试和分析。  相似文献   

8.
研究了新近开发的纳米晶(Fe90Zr3.5Nb3.5B3)95Cu1Si4合金的微组织和软磁性能.采用XRD、TEM和Mssbauer谱仪观察了合金的微组织变化,采用直流软磁测量设备测量了软磁性能.结果显示,合金是纳米晶相、残余非晶相和中间相的混合.软磁性能随着退火温度的变化而变化,且中间相的体积分数会影响软磁性能.当813K退火0.5h后,纳米晶相体积分数为40%,软磁性能最佳,此时BS最大为1.56T,HC达到最小为1.79A/m.  相似文献   

9.
 Fe Cr系软磁合金是一种抗蚀软磁材料。在Fe 13%Cr和Fe 17%Cr中添加不同含量的钼,对合金的抗点蚀、盐雾腐蚀、浸泡腐蚀以及大气腐蚀的能力和相应的磁性能进行了系统、全面的研究。结果表明,在这两种软磁合金中加入质量分数为20%和30%的钼,可明显提高合金的耐蚀能力;合理控制钼含量和采用相应的热处理工艺对合金磁性能的影响并不明显。  相似文献   

10.
Fe-Mn合金具有良好力学性能的同时,还具有较高的阻尼性能,因此被认为是一种非常具有应用前景的高阻尼合金,并可用于结构和汽车零部件.为了研究冷变形对Fe-Mn合金阻尼性能的影响,通过室温拉伸的方法,对Fe-19Mn合金进行了变形量为0?15%的冷变形处理.采用动态机械分析仪(DMA)对变形前后的Fe-19Mn合金的阻尼...  相似文献   

11.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
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。  相似文献   

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13.
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   

14.
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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16.
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   

17.
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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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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