共查询到17条相似文献,搜索用时 62 毫秒
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形状记忆合金由于其优良的超弹性和形状记忆效应而在医学上有着广泛的应用,其中由于NiTi形状记忆合金相较其它形状记忆合金具有更好的超弹性和生物相容性而得到了广泛的应用。但由于镍元素的毒性,使得开发一种生物相容性更好、无镍且具有良好力学性能的形状记忆合金成为必需。Ti-Mo-V-Nb-Al五元合金就是为此而开发的一种新型形状记忆合金。本研究用X射线衍射(XRD)、透射电子显微镜(TEM)和高分辨电子显微镜(HREM)研究了不同热处理条件对Ti-Mo-V-Nb-Al形状记忆合金微观结构的影响。 相似文献
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Ag对Sn-Pb电子钎料合金性能的影响 总被引:2,自引:0,他引:2
研究了Ag的合金化对Sn-Pb钎料合金材料性能的影响。并从钎料的润湿性能,机械性能及抗腐蚀性能等方面讨论了Ag的有利作用,研究表明,在一些特定条件下的电子元件的焊接,Sn-Pb-Ag钎料可部分地或全部地替代昂贵的遗金属钎料合金。 相似文献
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用sol-gel法在玻璃基片上分别制备了不同Al浓度掺杂和Al梯度掺杂的掺铝氧化锌(AZO)薄膜,并研究了分层退火和一次性退火对薄膜结构和性能的影响.结果表明:梯度掺杂与分层退火都能促进薄膜的(002)择优取向.Al掺杂摩尔分数为1.5%的薄膜和经分层退火处理的Al梯度掺杂的薄膜在395 nm处均有很强的紫外发射峰,但... 相似文献
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通过金属有机物热分解法制备了结构为Ag/NTC/SiO_2/Si的薄膜NTC(负温度系数)热敏电阻,研究了Cu掺杂对Cu_xMn_(1.56)Co_(0.96)Ni_(0.48)O_(4+y)[x=0~0.25,(x+3)/(4+y)=3/4]薄膜结构和性能的影响,并对其导电机理进行了分析。结果表明,少量Cu(x≤0.2)掺杂可以迅速降低薄膜的室温电阻值,过量则会导致薄膜产生孔隙和缺陷; Cu主要以Cu~+形式存在并占据A位;随着Cu掺杂量的增加,会使Cu~+和Mn~(3+)/Mn~(4+)离子对的含量占比均增加,促进两种电子跳跃机制导电。当x=0.2时,薄膜电阻有最佳的性能:R_(25)=0.082 MΩ,B_(25/50)=3250 K。 相似文献
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采用匀胶机旋转涂成膜的方法,在手套箱中制备PEDOT聚对苯乙烯磺酸(PSS)薄膜。详细研究了退火和掺杂对薄膜电学特性的影响,结果发现,在本实验范围内,薄膜的电导率随退火的温度和时间增加均呈现出最大值,这与薄膜的表面形貌是密切相关的;并且,由于材料的亲水性,导致真空下比N2和空气条件下退火薄膜的电导率要高;通过掺杂N,N-二甲基甲酰胺(DMF)和乙二醇,使薄膜的电导率提高了近3个量级。 相似文献
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Hydrogenated silicon carbide films (SiC:H) were deposited using the electron cyclotron resonance plasma chemical vapor deposition
(ECR-CVD) method from a mixture of methane, silane, and hydrogen, with diborane as the doping gas. The effect of changes in
the percentage of the diborane to reactant gas mixture on the deposition rate, optical bandgap, and photoconductivity were
investigated. There is evidence from Raman scattering analysis to show that films deposited at a low microwave power of 150
W were all amorphous and the bandgap decreases as the diborane level is increased whereas films deposited at a high microwave
power of 800 W at low diborane levels are highly photoconductive and contain microcrystalline silicon inclusions. These films
become amorphous as the diborane level is increased, while the optical bandgap remains relatively unaffected throughout the
entire range of diborane levels investigated. The effect of the microwave power was also investigated. The conductivity increases
rapidly to a maximum, followed by rapid reduction at high microwave powers. Raman scattering analysis showed evidence of the
formation and increase of microcrystalline silicon inclusions and diamond-like components in the films, the former of which
could account for the rapid increase and the latter the subsequent decrease in the conductivity. 相似文献
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J. J. Wang T. Omori Y. Sutou R. Kainuma K. Ishida 《Journal of Electronic Materials》2004,33(10):1098-1102
The effects of grain size, volume fraction of the α (fcc) phase in the β (bcc) matrix, and thermal stability on low thermal
expansion (LTE) properties of Cu-Zn-Al shape memory (SM) alloys induced by cold rolling were investigated by dilatometry,
optical microscopy, differential scanning calorimetry, and electrical conductivity measurements. The alloys with the larger
grains showed a superior two-way memory (TWM) effect, wider LTE temperature intervals with excellent thermal stability under
80°C. The α+β two-phase alloys also exhibited a good combination of cold workability and LTE properties. These results suggest
that the Cu-Zn-Al alloys with high electrical conductivity of about 20% International Annealed Copper Standard (%IACS) have
high potential as a new class of Invar alloys that can be applied in various fields. 相似文献
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Bismuth doped tin sulfide (SnS:Bi) thin films were deposited onto glass substrates by the spray pyrolysis technique at the substrate temperature of 350 °C. The effect of doping concentration [Bi/Sn] on their structural, optical and electrical properties was investigated as a function of bismuth doping between 0 and 8 at%. The XRD results showed that the films were polycrystalline SnS with orthorhombic structure and the crystallites in the films were oriented along (111) direction. Atomic force microscopy revealed that the particle size and surface roughness of the films increased due to Bi-doping. Optical analysis exhibited the band gap value of 1.40 eV for SnS:Bi (6 at%) which was lower than the band gap value for 0 at% of Bi (1.60 eV). The film has low resistivity of 4.788×10−1 Ω-cm and higher carrier concentration of 3.625×1018 cm−3 was obtained at a doping ratio of 6 at%. 相似文献