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为了提高合金的放电容量和高倍率放电性能,通过球磨Zr7Ni10合金对Zr0.5Ti0.5Mn0.7V0.2Co0.1Ni1.2合金表面进行改性,并研究了不同Zr,Ni10量和球磨时间对合金的相结构和电化学性能的影响。当采用8%(质量分数)Zr,Ni10进行球磨1h后,合金仍保持晶态,在50mAh/g电流条件下经过9次循环达到最大放电容量266mAh/g,比未球磨合金提高了约20%,而且在300mA/g电流条件下仍能保持最大放电容量的85%。随着球磨时间的增加,合金逐渐转为非晶态,合金的放电容量也迅速降低。非晶化合金在800℃进行热处理后大部分重新晶化,经过22次循环达到最大放电容量200mAh/g。 相似文献
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Active brazing is a commonly used method for joining ceramic materials. In the present study, the wetting behavior of four Ti-rich ternary Ni–Ti–Zr alloys was investigated through sessile drop experiments on alumina disks of 96 and 99.9 % purity. The microstructure at the metal/alumina interface was analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy. Three of the analyzed alloys exhibited reactive wetting with final contact angles between 40° and 70°. The reaction phases at the metal/alumina interface had a thickness of about 1 µm and were of a similar composition for all alloys. Dilatometer measurements showed thermal expansion coefficients between 13.2 and 15.8 × 10?6 °C?1. The lowest wetting angle of 40° was achieved with the alloy 61Ti–20Zr–19Ni at temperatures above 980 °C. 相似文献
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S. Kanagesan S. Jesurani R. Velmurugan T. Kalaivani 《Journal of Materials Science: Materials in Electronics》2012,23(4):952-955
M-type Hexaferrites B0.5Sr0.5Fe12−2x
Ni
x
Zr
x
O19 were synthesized and investigated. The XRD patterns show single phase of the magnetoplumbite barium strontium ferrite and
no other phases were present. The samples exhibit well defined crystallization; all of them are hexagonal platelet grains.
As the substitution level increased from x = 0.2 to 0.8 mol%, the grains are agglomerated and the average diameter increased. This suggests that Ni–Zr substitution
increases the grain size, as observed in the FE-SEM micrographs. The results of magnetic measurement revealed that Ms of barium strontium hexaferrite increased when the value of x increased from 0 to 0.4 mol% and then decreased with the increasing Ni–Zr content. The Hc decreases remarkably with increasing Ni and Zr ions content. Hard magnetic material is converted into soft magnetic material
when the substitution level is increased from 0.2 to 0.8 mol%. In particular, Ba0.5Sr0.5Fe12−2x
Ni
x
Zr
x
O19 with x = 0.2, 0.4, 0.6, 0.8 mol% has suitable magnetic characteristics with particle size small enough for high-density magnetic
recording applications. 相似文献
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运用真空电弧炉熔炼合金制备试样,采用三种不同的方法对金属熔体进行处理,试样的X射线衍射晶化相分析结果表明,B2O3和Na2SiO3的混合物与所选组分的熔体发生了反应,不适合作Zr基合金的包裹物;组分为CaF2(45%),AlF3(50%),CaO(5%)以及微量的TiO2的氟盐,由于该净化剂与所选的组分发生了反应,不适合Zr基合金的净化;设备的高真空度、原材料成分的高纯度是促进合金形成非晶态的重要因素。 相似文献
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研究了三元Ti38Zr45Ni17准晶合金及其V合金化后的四元合金(Ti0.38Zr0.45Ni0.17)100-xVx(x=5%、10%、30%、40%、60%(原子分数))的吸放氢性能.准晶成分设计思想源自于团簇线方法,即在Ti-Zr-Ni三元合金体系中利用两条团簇线的交点确定最佳准晶成分Ti38Zr45Ni17.利用铜模吸铸快冷工艺制备直径为3mm的合金棒.吸放氢测试结果表明,Ti38Zr45Ni17准晶在303K首次吸氢量为0.9%(质量分数),在573K时合金首次吸氢量可达2.38%(质量分数),合金吸氢过程快速完成,并放出大量的热,可将吸氢前的粉末样品烧结成块体凝聚物.吸氢后准晶结构消失,完全转化为氢化物结构.添加5%~30%(原子分数)的V进行合金化时可提高合金在573K下的首次吸氢量,最大为2.96%(质量分数);具有固溶体结构的(Ti0.38Zr0.45Ni0.17)40V60合金在室温下首次吸氢量为3.2%(质量分数).由于准晶及其V合金化的合金在吸放氢之后均形成了稳定的氢化物,导致其放氢非常困难. 相似文献
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用渗流铸造法制备Zr55Al10Ni5Cu30非晶复合材料 总被引:7,自引:0,他引:7
用渗流铸造法制备出以Zr55Al10Ni5Cu30合金为基体,以W丝束为增强相的大块非晶复合材料,采用X-射线衍射分析了基体的相组成,在扫描电镜(SEM)下观察了反应界面的形貌,利用电子探针研究了元素的迁移情况,通过改变渗流温度和时间。研究了W丝和基体间界面的作用过程,选择适当的渗流温度和时间,可以制备出长65mm直径4.3mm的大块W丝束增强Zr55Al10Ni5Cu30非晶复合材料,在一定范围内提高渗流温度降低渗流时间或降低渗流温度延长渗流时间能得到同样的结果,在渗流铸造前,液态金属的过热有利于提高基体的非晶形成能力,降低渗流铸造时产生的缺陷。 相似文献
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《材料与设计》2015
The glass-forming ability (GFA) of Ti–Zr–Be ternary alloys is dramatically improved by partially replacing Be with Ni. Centimeter-scale fully amorphous samples can be obtained in a wide Ni content range of 4 at.%–12 at.%. In particular, some of the developed Ti–Zr–Be–Ni alloys exhibit a critical diameter up to 20 mm, which is larger than that of other quaternary Ti-based bulk metallic glasses (BMGs). Moreover, Ni addition also enhances the yield strength and compressive plastic strain of Ti–Zr–Be alloys obviously. Based on the experimental results, the effect of substituting elements addition on the glass-forming ability of Ti–Zr–Be alloys has been systematically investigated and an empirical composition design method for the development of novel Ti-based BMGs with large GFA has been proposed. 相似文献
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The effect of pressure on the variation of the crystallization phases of the Zr55u30Al10Ni5 bulk glass and its thermal stability under high pressure annealing was investigated by X-ray diffraction (XRD)and differential scanning calorimeter(DSC).The mode of crystallization and products of crystallization of the Zr55Cu30Al10Ni5 bulk glass were quite different pressure.At ambient pressure,the crystallization products consisted of NiZr2 and CuZr2,while at pressure of 1 Gpa and 3 Gpa,the alloys crystallized into NiZr2 and Cu10Zr7,respectively.The alloy was nearly not crystallized and only a small amount of Cu10Zr7 was precipitated under 5 Gpa.DSC proved that the mode of the crystallization under high pressure was different from that at ambient pressure. 相似文献
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《Materials Letters》2004,58(7-8):1246-1250
Bulk amorphous Zr55Al10Cu30Ni5−xPdx (x=0, 5at.%) alloys were produced by copper mould casting. The microstructure of samples was characterized by X-ray diffraction (XRD). The corrosion resistance of the bulk amorphous alloys was studied by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS). The Pd-free alloy showed an active–passive transition by anodic polarization in 3.5% NaCl solution, it was spontaneously passive and had a wide passive region with significantly low passive current density. The 5% Pd amorphous alloy shows a single active state even with a limited passive region. X-ray photoelectron spectroscopy (XPS) analysis revealed that the spontaneous passive films formed on the alloys after immersion in 0.6 M NaCl solution for 72 h were composed of the oxidation of Zr, Al and Cu element. The Pd-free and 5% Pd alloys show excellent corrosion properties in 1 M NaOH solution. 相似文献
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为了提高内燃机用镍基合金表面(Pt,Ni) Al涂层的抗氧化性能,对镍基单晶高温合金DD6表面Pt-Zr镀层实施气相渗铝得到Zr改性(Pt,Ni) Al涂层,对比分析了此涂层与常规(Pt,Ni) Al涂层的热腐蚀测试结果。结果表明:涂层改性后Zr元素基本固溶于中间层以及外层(Pt,Ni) Al组织相内,未改性和改性后涂层都是由PtAl2与Ni Al共同构成,涂层内的PtAl2相都以弥散态的形式存在于(Pt,Ni) Al相中;经过100 h热腐蚀测试后Zr改性(Pt,Ni) Al涂层比未改性涂层的增重程度更低;涂层进行60 h热腐蚀形成的表层中包含了Al2O3与Ni Al,并且涂层内PtAl2相含量减少;经Zr改性后的(Pt,Ni) Al涂层发生了少量内氧化,实际腐蚀深度减小。 相似文献
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