共查询到17条相似文献,搜索用时 62 毫秒
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在柔性衬底上制备的Bi-2212(Bi2Sr2CaCu2O8+x)超导厚膜在高场低温下有高的临界电流密度、可塑性好、易加工成材等特点,因而有广阔的应用前景.所以制备低成本、高性能的Bi-2212厚膜技术已经成为此类高温超导材料实用化的关键.本文系统的研究了采用Bi系超导粉前驱化学溶液的方法进行Bi-2212超导厚膜的制备和表征.对制备超导厚膜过程中的关键步骤做了系统的研究,主要包括局部熔融烧结温度、固相烧结温度、匀胶机最高转速、涂层的厚度等对超导转变温度和转变宽度的影响.我们得出最佳的烧结温度和固相温度分别是888℃、845℃,并发现随着匀胶机转速和涂层厚度的增加,超导膜的转变温度逐步提高,当最高转速为4000r/min,涂层厚度设定为七层,制备出的超导膜R~T曲线的第二个相转变点消失了.制备出的超导膜的转变温度在90K左右.与此同时还进行了XRD、SEM测试表征.最终可以得到均匀平整无裂纹的高质量Bi-2212超导厚膜. 相似文献
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用于限流器的Bi-2212超导筒的研制 总被引:2,自引:0,他引:2
采用部分熔化法在流氧气氛的旋转炉中 ,以 Ag箔为衬 ,成功制得直径 60 mm的 Bi- 2 2 1 2超导圆筒。加热初始粉到部分熔融状态 ,然后再冷却到 855℃以形成超导相 ,在富 N2 气氛下退火 ,并且从 70 0℃开始在纯 N2 气氛中冷却 ,这种工艺可以得到较好机械强度和外型的筒。XRD图象表明 Bi- 2 2 1 2筒中主要相为 Bi- 2 2 1 2超导相。 Bi- 2 2 1 2筒的临界电流密度为 1 0 0 Acm-2 ,Ic约为1 0 A 相似文献
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为探究加强型Bi-2212超导股线的力学性能以及不锈钢包带对超导股线力学性能的影响,运用Ansys软件建立加强型Bi-2212超导股线的三维模型,采用有限元分析方法,对其机械结构进行仿真,模拟高温高压热处理后轴向受拉形变量和应力应变分布情况。仿真结果显示,在同样施加100 N拉力的情况下,与超导原线(Bi-2212超导线)相比,密绕Ni80Cr20包带后的加强型Bi-2212超导股线轴向受拉形变程度减小,约10%;应力应变均降低,约30%。采用Ni80Cr20作为外包带制成的加强型Bi-2212超导股线力学性能显著,是未来超导线发展方向之一。 相似文献
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高温超导材料Bi-2212在4.2 K具有优异的磁场载流性能。是目前高场下(20 T)最具应用前景的高温超导材料之一。高压热处理工艺是决定Bi-2212超导线材性能的重要因素。通过分析不同压力强度(主要为3 MPa和5 MPa)下Bi-2212超导线材的线径、临界电流以及n值特性,研究了不同压强对热处理炉恒温区以及压强对超导材料性能的影响规律。结果表明,3 MPa压力下与5 MPa压力下热处理后对Bi-2212线材性能的影响相近,3 MPa的压强更容易实现,对设备要求更低。 相似文献
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选择成分均为72%γAl2O3+28%SiO2的氧化铝纤维制品作为Bi-2212超导磁体绝缘纤维材料并进行空气热处理除碳。采用强度测试、SEM、TG-DSC等测试手段,对三种氧化铝纤维制品(宽25mm/厚0.2mm氧化铝纤维带A、宽25mm/厚0.35mm氧化铝纤维带B和200tex/3股/捻度80氧化铝纤维束C)的热失重、纤维表面形貌、纤维强度进行分析表征。结果表明,其耐温性好,热失重过程并未发现晶相转变的吸放热峰。纤维经过空气热处理后,表面浸润剂氧化挥发,纤维裸露,无缺陷暴露,直径变化不明显,强度下降不超过25%,绝缘性能提高。分析结果表明,通过600℃、2h空气热处理可以有效提高氧化铝纤维绝缘性能。 相似文献
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A model of knock-out of oxygen by charged particle (α and proton) irradiation of Bi2Sr2CaCu2O8+x
(Bi-2212) is proposed on the basis of Monte Carlo TRIM calculations. In Bi-2212, the loosely bound excess oxygen is vulnerable
to be displaced by particle irradiation. Binding energy and hence, displacement energy of this loosely bound excess oxygen
is less compared to that of stoichiometric lattice bound oxygen and other atoms. The displaced or knocked out oxygen goes
to pores or intergranular region and generates large pressure inside the sample. Because of porosity of the material, this
displaced oxygen diffuses out and there is a net reduction of oxygen content of the sample. The irradiation induced oxygen
knock-out is dominant in the bulk where nonionizing energy loss is maximum. 相似文献
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M. Fujiwara T. Makino T. Nakabayashi H. Tanaka K. Kinoshita S. Kishida 《Physica C: Superconductivity and its Applications》2009,469(15-20):1178-1181
We compared the crystallinity of the Bi-2212 single crystals grown by the horizontal Bridgman (HB) method with those grown by the vertical Bridgman (VB) method in terms of resistivity, ρ. It was clarified that crystals far inside the ingot grown by HB method showed the equivalent crystallinity to crystals grown by VB method, whereas crystals near the surface of the ingot grown by HB method showed the similar crystallinity to crystals grown by TSFZ method, which is sensitive to the growth atmosphere. 相似文献
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T. Kiss V. S. Vysotsky H. Yuge H. Saho Yu. A. Ilyin M. Takeo K. Watanabe F. Irie 《Physica C: Superconductivity and its Applications》1998,310(1-4):372-376
Using a Bi-based small high Tc superconductor (HTSC) coil, we have studied its stability against a local disturbance and current-induced quench in the helium gas cooling condition. While the stability margin of HTSC coil against a local disturbance was very large, quench current was limited by a catastrophic temperature rise which originated from the nonlinear characteristic of the Joule heating. The crucial parameter for the quench becomes the nonlinear resistance in HTSC as a function of temperature and transport current. It has been shown that the dynamic characteristics of the quench can be described quantitatively by the simplified one-dimensional heat balance equation. 相似文献