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涂层超导是目前国际超导界的研究热点和重点,所采用的韧性金属基带多为Ni和NiW合金.本文采用粉末冶金方法制备了Ni-3 at.%W和Ni-5 at.%W合金.利用轧制辅助双轴织构基带(咖TS)技术制备了Ni-W合金基带,系统研究了Ni-W合金形变和再结晶织构转变规律.研究表明:通过大变形量的冷轧和高温再结晶退火,可以得到强立方织构的Ni-W合金基带. 相似文献
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为了制作能满足YBCO涂层导体(coated conductor)所需要的高强度、低磁性的立方织构基带,本工作用粉末冶金方法制作了Ni-5at%W合金基带.为评估基带中立方织构的发展,用March-Dollase函数对各种热处理样品的择优取向度进行了研究,结果与用X射线极图法和电子背散射衍射法得到的结果基本一致.研究结果表明,在实验中所用的工艺参数范围内,随总加工率和热处理温度的提高,基带中立方织构百分数明显增高.提高总加工率实际增加了冷加工样品中立方织构晶粒或立方核心的数量.实验中得到了较好的和实用的工艺制度,用这种工艺可以制作出具有99%~100%立方织构百分数,并具有很好一致取向度的Ni5W基带. 相似文献
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为了制作能满足YBCO涂层导体(coated conductor)所需要的高强度、低磁性的立方织构基带,本工作用粉末冶金方法制作了Ni-5at%W合金基带.为评估基带中立方织构的发展,用March-Dollase函数对各种热处理样品的择优取向度进行了研究,结果与用X射线极图法和电子背散射衍射法得到的结果基本一致.研究结果表明,在实验中所用的工艺参数范围内,随总加工率和热处理温度的提高,基带中立方织构百分数明显增高.提高总加工率实际增加了冷加工样品中立方织构晶粒或立方核心的数量.实验中得到了较好的和实用的工艺制度,用这种工艺可以制作出具有99%~100%立方织构百分数,并具有很好一致取向度的Ni5W基带. 相似文献
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通过差热分析研究成分变化对YBa2Cu3O7-δ/Y2BaCuO5(YBCO)高温超导织构体系列的熔化温度和固化反应温度的影响,结合排推效应所产生的成分不均匀性,分析了超导体初始组分为YBa2Cu3O7-δ+xY2O3的织构生长极限。发现含约6-7wt%(或50mol%)CuO时,固化温度出现明显极小值。 相似文献
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采用X射线衍射测试极图、使用专用软件计算织构取向分布函数(ODF), 研究了热轧后454℃×4h再结晶退火的直接铸造5052铝合金板(DC 5052)和双履带连续冷却铸造5052铝合金板(CC 5052)冷轧制到不同压下量的试样,自表层至心部层的冷轧织构分布差别,为工业上生产及应用DC 5052与CC 5052铝合金冷轧板提供依据。结果显示:同样的大压下量时CC 5052的β织构强度及体积分数高于DC 5052的。冷轧前CC 5052的再结晶织构Cube的体积分数小于DC 5052的,剩余位向的体积分数多于DC 5052的,导致CC 5052表层的β织构强度及体积分数达到与1/4层、中心层接近所需要的冷轧压下量比DC 5052试样需要的小。CC 5052冷轧板冲压加工方面的性能优于DC 5052冷轧板。 相似文献
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Cobalt doped ZnO films are synthesised using a hydrothermal process. The effect of Co2+ concentration on morphology, phase composition, crystallisation and spectroscopic characteristics of ZnO films is investigated. The results indicate that both the structure and morphology of the ZnO films evolve with the concentration of cobalt ions incorporated into the lattice. In the presence of a small amount of Co2+ ions, films are formed that comprise hexagonal ZnO nanorods, oriented with the c-axis perpendicular to the substrate. With increasing amount of Co2+, cracks in the ZnO nanorods can be observed and growth in the [0 0 1] direction is significantly inhibited. When the Co2+ concentration exceeds 0.010 M, ZnO rods with the typical hexagonal structure are no longer observed and instead, ZnO films comprising close-packed grains with an irregular polygonal structure are formed. The epitaxial growth of ZnO films is nearly completely inhibited when the concentration of Co2+ is increased above 0.050 M. This behaviour can be explained by the selective adsorption of the organic substances in the solution onto the (0 0 1) ZnO crystal face, thus inhibiting growth in the [0 0 1] direction and disrupting the crystallisation of ZnO films. Increasing the Co content deteriorates the crystallisation of ZnO rods and increases tensile stresses present in the ZnO films. 相似文献
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Pyrite thin films were prepared by the sol-gel dip coating process and sulfuration treatment. The evolution of crystal orientation for the pyrite films was investigated as a function of sulfuration temperature. And the effect of crystal orientation on the electrical and optical properties was studied. It was found that films show (1 1 1) preferred orientation after sulfurized at low temperature. However, the (2 0 0) and (3 1 1) mixed preferred orientations were observed when pyrite films were sulfurized at higher temperature. Experimental results also indicate that the carrier concentration is high when the films show (1 1 1) preferred orientation. And the optical absorption coefficient is also large when the films grow with (1 1 1) preferred orientation. It is speculated that surface free energy could play a more important role in determination of preferred orientation when films were sulfurized at low temperature. However, the strain energy plays a more important role in determination of preferred orientation when films were sulfurized at higher temperature. 相似文献
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LBO晶体上ZrO2薄膜的显微结构和光学性质 总被引:2,自引:0,他引:2
用电子束蒸发方法在三种不同取向的三硼酸锂(LiB3O5,简称LBO)晶体上沉积了ZrO2薄膜.采用分光光度计和X射线衍射技术对LBO晶体基底结构对薄膜光学性质和显微结构的影响进行了研究.实验结果表明基底结构对薄膜的显微结构和光学性质具有明显影响,即X-LBO,Y-LBO和Z-LBO上沉积的ZrO2薄膜分别沿m(-212),m(021)和o(130)择优生长,且m(021)择优取向的ZrO2薄膜具有最高的折射率和最小的晶格不匹配. 相似文献
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采用直流磁控溅射方法制备膜厚为50, 100, 200, 400, 600 nm的Nb薄膜,对薄膜的沉积速率、表面形貌、晶体结构进行了研究,并对其应力和择优取向进行了详细的分析。原子力显微镜图像显示Nb膜表面光滑、致密,均方根粗糙度达到0.1 nm量级。X射线小角衍射给出了薄膜的晶格结构、晶粒尺寸和应力情况。分析表明薄膜为多晶体心立方结构(bcc),在(110)晶面方向存在明显的择优取向,且随着薄膜厚度增大而增强。Nb膜应力先随薄膜厚度增大而增大,在200 nm时达到最大值(为1.015 1 GPa),后随薄膜厚度的增大有所减小。 相似文献
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Cubic boron nitride (c-BN) films are prepared by the radio frequency magnetron sputtering technique. The stresses and crystallinities of the films are estimated by the Fourier transform infrared spectroscopy of c-BN samples, including the peak shifts and varieties of full widths at half maximum. The effects of the B-C-N interlayer and the two-stage deposition method on the c-BN films are investigated. Then the thick and stable c-BN films are prepared by a combination of the two methods. The properties of the interlayer and film are also characterized. 相似文献
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A combinatorial sputter coating system has been developed that can optimize the crystal preferred orientation of coating films. With this system, it is possible to synthesize various kinds of coatings whilst precisely controlling conditions such as the sputter gas, the gas pressure, the gas partial pressure, the r.f. power, the substrate temperature, the distance between the substrate and target, etc. In this way, we successfully synthesized copper oxide coatings with different crystal preferred orientations, and low frictional property was obtained by optimizing the crystal preferred orientation. 相似文献
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Investigation of ultra—thin ferromagnetic films with a simple cubic lattice 总被引:1,自引:0,他引:1 下载免费PDF全文
Using Green‘s function method,we investigate ferromagnetic films with a simple cubic lattice containing up to ten monolayers.The Hamiltonian includes the Heisenberg exchange term,surface anisotropy (SA) and dipole interaction (DI).We calculate the magnetization as a function of temperature and film thickness,and we analyse the behaviour of spin canting.The result is in agreement with experiments.We calculate phase diagrams of SA versus DI to show the conditions under which spontaneous magnetization can occur.As a special case,we discuss the Heisenberg model without SA and DI. 相似文献