王苹梅柄初雷零
腐蚀学报（英文）
用热压的方法合成了若干MAX相化合物，包括相（Ti2AlC和Ti2AlN）和312相（Ti3SiC2和Ti3AlC2）;研究了它们在1 mol/L HCl、1 mol/L NaOH和1 mol/L H2SO4中的电化学性质及其结构与其稳定性的关系.结果表明:在所有溶液中,312型MAX相比211相更稳定;Ti3SiC2 和Ti3AlC2几乎在所有溶液里都发生钝化，而Ti2AlC和Ti2AlN在1 mol/L HCl中活跃地溶解，还伴有大量气泡产生；Ti3SiC2比Ti2AlC、Ti2AlN 和Ti3AlC2更稳定.
关键词:
MAX相
,
polarization curves
,
electrochemical behavior
王苹
,
梅炳初
,
雷零
腐蚀学报（英文）
doi:10.3969/j.issn.1002-6495.2009.01.014
用热压的方法合成了若干MAX相化合物,包括211相(Ti2AlC和Ti2AlN)和312相(Ti3SiC2和Ti3ALC2);研究了它们在1 mol/L HCl、1 mol/L NaOH和l mol/L H2SO4中的电化学性质及其结构与其稳定性的关系.结果表明:在所有溶液中,312型MAX相比211相更稳定;Ti3SiC2和Ti3AlC2几乎在所有溶液里都发生钝化,而Ti2AlN在1 mol/L HCl中活跃地溶解,还伴有大量气泡产生;Ti3SiC2比Ti2AlC、Ti2AlN和Ti3AlC2更稳定.
关键词:
MAX相
,
极化曲线
,
电化学性质
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
Journal of Nanoscience and Nanotechnology
In this paper, we reported tie oxidation behaviour of Ti(2)AlN films on polycrystalline Al(2)O(3) substrates. The Ti(2)AlN films composed mainly of nanolaminated MAX phase was obtained by first depositing Ti-Al-N films using reactive sputtering of two elemental Ti and Al targets in Ar/N(2) atmosphere and subsequent vacuum annealing at 800 degrees C for 1 h. The Ti(2)AlN films exhibited excellent oxidation resistance and thermal stability at 600-900 degrees C in air. Very low mass gain was observed. At low temperature (600 degrees C) no oxide crystals were observed on film surface. Blade-like theta-Al(2)O(3) fine crystals formed on film surfaces at 700-800 degrees C. At high temperature (900 degrees C), firstly theta-Al(2)O(3) formed on film surface and then transformed into alpha-Al(2)O(3). At 700-900 degrees C, a continuous Al(2)O(3) layer formed on Ti(2)AlN films surface, acting as diffusion barrier preventing further oxidation attack. The mechanism of the excellent oxidation resistance of Ti(2)AlN films was discussed based on the experimental results.
关键词:
Ti(2)AlN;Nanolaminated MAX Phase;Films;Oxidation;thin-films;mechanical-properties;m(n+1)ax(n) phases;stability;ti3sic2;air;1st-principles;transformation;corrosion;ceramics
朴燕
,
郑喜凤
,
刘维亚
,
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
,
电源电路
,
正极性
,
负极性
