Gerhard Sauthoff(Max-Planck-Institut fur Eisenforschung GmbH.
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D-40074 Dusseldorf
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Germany)
金属学报(英文版)
Intermetallics for structural applications at high temperatures must show a sufficient high temperature strength which is controlled by creep processes. In the first section the creep behaviour of single-phase intermetallic alloys is overviewed with respect to stress and temperature dependence and effects of composition and microstructure. It is shown in particular that creep deformation is controlled by diffusion. The second section refers to multiphase intermetallic alloys, and both particulate and non-particulate alloys are regarded. Data are presented for single-phase and multiphase alloys based on B2 phases and lesscommon phases and the consequences of diffusion control for alloy design are discussed.
关键词:
:creep
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null
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null
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null
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Scripta Materialia
Nb(4)AlC(3), a new compound belonging to the MAX phases, was discovered by annealing bulk Nb(2)AlC at 1700 degrees C. The crystal structure of Nb(4)AlC(3) was determined by combined X-ray diffraction, high-resolution transmission electron microscopy and ab initio calculations. It was reported that Nb(4)AlC(3) follows the Ti(4)AlN(3)-type crystal structure. The lattice constants are a = 0.31296 nm, c = 2.41208 nm and the atomic positions are Nb1 at 4f (1/3, 2/3, 0.0553), Nb2 at 4e (0, 0, 0.1574), Al at 2c (1/3, 2/3, 1/4), C1 at 2a (0, 0, 0) and C2 at 4f (2/3, 1/3, 0.1086). (c) 2007 Published by Elsevier Ltd. on behalf of Acta Materialia Inc.
关键词:
Nb(4)AlC(3);ceramics;crystal structure;thin-films;ti3sic2;ti4aln3;ta4alc3;microstructure;deformation;carbides;ti3alc2;growth
朴燕
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郑喜凤
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刘维亚
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王瑞光
液晶与显示
doi:10.3969/j.issn.1007-2780.2000.02.008
液晶显示器在信息显示技术中得到了越来越广泛的应用.作为液晶显示的主要部分之一的电源电路,直接控制提供给液晶驱动芯片的偏压.电源电路的电压的高低将直接影响液晶显示器的灰度调整和对比度的变化.MAX686是Maxim公司生产的用于提供液晶偏压的电源器件.MAX686能够转换液晶所需的正极性或负极性偏压的集成电路,有很强的灵活性,其内部有6bit的数模转换器,可用数字方式调整输出电压.因此,可以很方便地用软件或硬件来调整输出电压.MAX686的高集成度为其节省了体积,减小了功耗,增加了电池的寿命,使其非常适用于电池供电的便携式仪器中.
关键词:
液晶驱动
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电源电路
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正极性
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负极性
Journal of the American Ceramic Society
A new-layered compound, (Ti(0.5)Nb(0.5))(5)AlC(4), which belongs to MAX phases was discovered. The new-layered carbide was synthesized by reactive hot pressing of Ti, Nb, Al, and C powders. The crystal structure was determined by the combination of X-ray diffraction and transmission electron microscopy analyses, which consists of a 5(Ti, Nb)-C bond chain linked by an Al layer. The lattice parameters are a=3.100 A, c=28.89 A, with Ti(Nb)1 at (0, 0, 0), Ti(Nb)2 at (1/3, 2/3, 0.0877), Ti(Nb)3 at (2/3, 1/3, 0.1723), Al at (0, 0, 0.25), C1 at (2/3, 1/3, 0.0463), and C2 at (0, 0, 0.1566).
关键词:
crystal-structure;ternary ceramics;c system;carbide;ta4alc3;microstructures;ti3gec2;ti4aln3;solids
Journal of the American Ceramic Society
Reticulated porous Ti(3)AlC(2) ceramic, a member of the MAX-phase family (M(n+1)AX(n) phases, where M is an early transition metal, A is an A-group element, and X is carbon and/or nitrogen), was prepared from the highly dispersed aqueous suspension by a replica template method. Through a cathodic electrogeneration method, nanocrystalline catalytic CeO(2) coatings were deposited on the conductive porous Ti(3)AlC(2) supports. By adjusting the pH value and cathodic deposition current, coatings exhibiting nanocellar, nanosheets-like, or bubble-free morphologies can be obtained. This work expects to introduce a novel practically feasible material system and a catalytic coating preparation technique for gas exhaust catalyst devices.
关键词:
liquid reaction synthesis;electrochemical synthesis;dispersion;behavior;porous ceramics;silica sol;ti3alc2;thickness;powders;films
