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61.
Yaping KeLU 《材料科学技术学报》2002,18(6):492-496
In this paper,glass transition and thermal stability of the Zr-Al-Cu-Ni metallic glasses were investigated by using electrical resistance measurement(ERM),DSC and X-ray diffraction techniques.The experimental results show that the ERM is capable of detecting the glass transition of the amorphous alloys and can help to distinguish the crystallization products of the Zr-Al-Cu-Ni metallic glasses owing to the difference of the electrical resistivity between the precipitation phases. 相似文献
62.
63.
介绍了高频等参数感应的基本原理。以胜利油田比较典型的 3口井为例 ,详细分析了高频感应资料在划分薄夹层、确定储层流体饱和类型、评价储层电阻率空间分布等方面的应用。研究结果表明 ,高频感应具有极高的纵向分辨率和较好的径向探测特性 ,能够准确计算地层真电阻率、侵入带电阻率及侵入半径 ,通过与常规感应及薄层测井资料的对比 ,论证了高频等参数感应在测井技术应用上的优越性 相似文献
64.
Resilient metal spring silicone-matrix conducting composites for separable interconnections in electronics were fabricated
by the impregnation of silicone into a preform comprising randomly oriented C-shaped Cu-Be springs and a small proportion
of Sn-Pb solder, which served to connect the springs at some of their intersections. Composites containing 6.1-9.8 vol.% total
filler exhibited volume electrical resistivity 0.5-1.0 mΩ.cm and contact resistivity (with copper) 11-17 mΩ.cm2. A compressive stress of about 30 kPa was needed for the low contact resistivity to be reached. The volume 17-26% and the
contact resistivity increased by 5% after heating in air at 130-150°C for seven days. Composites containing <9 vol.% total
filler showed no stress relaxation for seven days at 6.0% strain. 相似文献
65.
Rui Morimoto Chisato Yokomori Akiko Kikkawa Akira Izumi Hideki Matsumura 《Thin solid films》2003,430(1-2):230-235
In this paper, bulk-Si metal–oxide–semiconductor field effect transistors (MOSFETs) are fabricated using the catalytic chemical vapor deposition (Cat-CVD) method as an alternative technology to the conventional high-temperature thermal chemical vapor deposition. Particularly, formation of low-resistivity phosphorus (P)-doped poly-Si films is attempted by using Cat-CVD-deposited amorphous silicon (a-Si) films and successive rapid thermal annealing (RTA) of them. Even after RTA processes, neither peeling nor bubbling are observed, since hydrogen contents in Cat-CVD a-Si films can be as low as 1.1%. Both the crystallization and low resistivity of 0.004 Ω·cm are realized by RTA at 1000 °C for only 5 s. It is also revealed that Cat-CVD SiNx films prepared at 250 °C show excellent oxidation resistance, when the thickness of films is larger than approximately 10 nm for wet O2 oxidation at 1100 °C. It is found that the thickness required to stop oxygen penetration is equivalent to that for thermal CVD SiNx prepared at 750 °C. Finally, complementary MOSFETs (CMOSs) of single-crystalline Si were fabricated by using Cat-CVD poly-Si for gate electrodes and SiNx films for masks of local oxidation of silicon (LOCOS). At 3.3 V operation, less than 1.0 pA μm−1 of OFF leakage current and ON/OFF ratio of 107–108 are realized, i.e. the devices can operate similarly to conventional thermal CVD process. 相似文献
66.
In keeping with the advance of more compact and more power-saving electronic equipment, the demand is increasing for smaller and more efficient switching power supply. Therefore, it is necessary to provide the adequate magnetic power ferrite materials to satisfy the demand. Such ferrite materials have to meet the following main requirement: 1) high initial permeability (μ i ); 2) high saturation magnetic induction (Bs); 3) high Curie temperature (Tc); 4) high electrical resistivity (ρ ); 5)… 相似文献
67.
68.
Structural and electrical properties of brush plated ZnTe films 总被引:1,自引:0,他引:1
Zinc telluride thin films were deposited by the brush plating technique at a potential of −0.90 V (SCE) on conducting glass and titanium substrates at different temperatures in the range 30–90 °C. The films were polycrystalline in nature with peaks corresponding to the cubic phase. Direct band gap of 2.30 eV was observed. XPS studiers indicated the formation of ZnTe. Depth profiling studies indicated a uniform distribution of Zn and Te throughout the entire thickness. EDAX measurements were made on the films and it was found that there was a slight excess of Te. The carrier concentration was found to vary from 1014–1015 cm−3 with increase of substrate temperature. The mobility was found to vary from 5 to 60 cm2 V−1 s−1. 相似文献
69.
N. I. Bobyr’ A. P. Grabovskii A. V. Timoshenko A. P. Khalimon 《Strength of Materials》2006,38(1):92-98
Within framework of the continual fracture mechanics, we describe the engineering approach to the assessment of scattered
microdamage accumulation kinetics in metallic materials under elastoplastic loading conditions in case of plane stressed state.
Automatized experimental stand and the respective investigation technique are discussed. The stand has been developed based
on modification of the UMé-10T electromechanic test machine. State-of-the-art computer technologies and microprocessing hardware
are incorporated in the stand automation. We present the technique of experimental assessment of damage accumulation kinetics
in metallic structural materials under complex elastoplastic loading conditions with account of two different fracture (cleavage
and shear) processes, which technique is based on measuring the specific electric resistance of the specimen.
__________
Translated from Problemy Prochnosti, No. 1, pp. 128–137, January–February, 2006. 相似文献
70.
B. Wilthan G. Pottlacher 《稀有金属(英文版)》2006,25(5):592-596
1. Introduction Metal working industry needs accurate thermo- physical properties of liquid metals and alloys as input data for different simulation routines to im- prove the performance of their products. Within this paper we continue the systematic investigation of the dependence of emissivity of binary alloys on the relative concentration of the constituent elements (for a previous paper see [1]). 2. Experimental method A fast ohmic pulse heating technique is applied to heat metallic wire-s… 相似文献