金属氢化物性质与应用

本文介绍了金属氢化物的性质与应用，与及国内外金属氢化物研究的最新动向。     

金属氢化物性质与应用

本文介绍了金属氢化物的性质与应用，与及国内外金属氢化物研究的最新动向。     

金属-玻璃复合材料的研究

金属-玻璃复合材料可用粉末冶金方法制取。本文阐述了金属-玻璃复合材料的性能及显微组织,并说明了这种复合材料的应用情况。     

美制造出单晶体结构铈铝金属玻璃

一般来说,包括金属玻璃在内的玻璃态物质在内部结构上都处于无序状态,但据美国每日科学网近日报道,美国的一个研究小组日前通过高压对一个金属玻璃样本进行处理后,在其内部发现了一个呈高度有序状态的单晶体结构。该研究有助于人们加深对金属玻璃材料的认识,开创出一种新型金属玻璃的制备工艺。相关论文发表在6     

新型金属玻璃研制成功

一种新型“金属玻璃”在美国研制成功。这代金属玻璃，以50％的铁，加上钼、钇、锰、碳、硼、铬和钴等化学元素混合而成。其主要突破在技术上，合金的玻璃形成能力大为增强。与过去相比，钇的加入使材料形成非晶态能力增强，同时合金的冷却速度放慢了许多；合成材料用的铁等元素比较便宜，成本较低；产品的尺寸增大。     

利用机械合金化生产的金属氢化物电极用MmNi5合金材料

综述了利用机械合金化和退火方法制备纳米晶体的ＭｍＮｉ５型合金及这些材料的室温组织和电化学性能，指出已取得了达到２０７ｍＡ．ｈ／ｇ放电能力的ＭｍＮｉ４．２Ａｌ０．８材料。     

燃料电池用金属氢化物贮氢罐的研究

金属氢化物贮氢罐是燃料电池的侯选氢源之一 ,由于其安全性好、体积贮氢密度高、提供的氢气纯度高 ,因此在小型燃料电池及某些特定环境 (如潜艇、电动铲车 )的应用中具有极强的竞争力。北京有色金属研究总院研制开发出可分别与 3kW ,2 0 0W及 30W燃料电池配套的多种类型贮氢罐 ,成功地应用在电动摩托车、电动自行车和手机上     

玻璃双毛细管雾化器氢化物——原子吸收微量铋的测定

本文主要介绍自制玻璃双毛细管雾化器用来测定微量铋。做了介质酸度、共存元素的影响及消除、工作曲线、样品处理的试验,试验结果表明,自制玻璃双毛细管雾化器,直接产生氢化物以空气—乙炔火焰测定,方法可靠,灵敏度高,不需要专门的氢化物发生器,也不需要惰性气体,雾化器可以互换,操作简单方便。     

铁基金属玻璃的热磁特性

本文利用振动样品磁强计、霍普金松效应、差热分析与双臂电桥等实验方法较系统地研究了类金属硼含量对Fe_(92-X)Cr_8B_x金属玻璃的饱和磁矩(σs)、Curie温度(T_c)、晶化温度(T_(cr)),室温电阻率(ρ)与(B-T)曲线等特性的影响规律。结果表明,Fe_(92-X)Cr_8B_X金属玻璃的(σs)、T_c与ρ在15≤x≤23范围内均随类金属硼含量的增加而呈现出线性增大的变化规律,而T_(cr)却无明显变化,Fe_(92-X)Cr_8B_X的磁感应强度(B)随测量温度(T)的升高呈现出线性缓慢降低的变化规律,其降低的幅度是随类金属硼含量的减少而逐渐增大。该成果对开发新型热磁开关等功能材料具有实用价值。     

金属玻璃中与氢有关的内耗

使用Bordoni型的仪器在声频范围内研究了铁镍基金属玻璃的低温含氢内耗,并研究了退火处理对内耗的影响。结果表明低温含氢内耗是Snoek 型弛豫,并观察到了反常模量亏损和反常弛豫强度现象,提出τ缺陷增强 Snoek 弛豫模型解释了反常弛豫强度现象。     

Corrosion Behavior of Fe-based Bulk Metallic Glass and In-situ Dendrite-reinforced Metallic Glass Matrix Composites in Acid Solution

The corrosion behavior study was conducted on a novel Fe_(77)Mo_5P_9C_(7.5)B_(1.5)in-situ metallic glass matrix composite(MGMC).This composite sample was developed by introduction of bccα-Fe dendrites as reinforcing phase.The corrosion behavior of this composite was compared to its monolithic counterpart and other Fe-based alloys such as 304 Land 2304Lstainless steels.The corrosion resistance of MGMCs in H_2SO_4 solution shows inferior to that of other Fe-based alloys.Experiments suggest that Fe-BMGs samples possess better corrosion resistance property than that of Fe-MGMCs.The possible underlying reasons can be the inhomogeneity induced by the precipitation ofα-Fe dendrites in the MGMCs.     

Kinetics of Glass Transition and Crystallization in Carbon Nanotube Reinforced Mg-Cu-Gd Bulk Metallic Glass

Mg65Cu25Gd10 bulk metallic glass and its carbon nanotube reinforced composite were prepared. Differential scanning calorimeter （DSC） was used to investigate the kinetics of glass transition and crystallization processes. The influence of CNTs addition to the glass matrix on the glass transition and crystallization kinetics was studied. It is shown that the kinetic effect on glass transition and crystallization are preserved for both the monothetic glass and its glass composite. Adding CNTs in to the glass matrix reduces the influence of the heating rate on the crystallization process. In addition, the CNTs increase the energetic barrier for the glass transition. This results in the decrease of GFA. The mechanism of the GFA decrease was also discussed.     

Ti基大块金属玻璃的研究与应用

阐述了Ti基大块金属玻璃(BMG)的成分设计原则及制备方法，并对Ti基非晶合金及其部分晶化复合材料的力学性能及断裂机理进行了评述。结果表明：Ti基大块金属玻璃具有较高的断裂强度、弹性延伸率及一定的塑性延伸率，而经过部分晶化获得的非晶合金基纳米颗粒复合材料，其室温塑性获得很大的改善。在此基础上探讨了该合金目前所存在的问题、研究热点以及其应用前景。     

含化合物金属熔体结构的共存理论及其应用

从含化合物金属熔体的原子本性和分子本性（活度的负偏差，混合△Ｇ和△Ｈ显示最小值，过剩稳定性的突然升高，电阻率显示最大值和相图等）出发，提出了反映本熔体实际的原子和分子共存理论。根据此理论的不同金属熔体作用浓度（即实测的活度）的计算模型。计算结果与实际符合的事实证明，共存理论恰当地反映了含化合物金属熔体的结构本质。     

Rate Dependence of Serrated Flow and Its Effect on Shear Stability of Bulk Metallic Glasses

The rate dependence of serrated flow and its effects on the stability of shear banding were systematically investigated in a prototypic bulk metallic glass.It was found that with the increase of external strain rate,the serra-ted flow is gradually suppressed and could completely disappear at a critical strain rate.The serration size,character-ized by the mean stress drop amplitude,decreases inversely with the strain rate,while the waiting time for serration decreases with the strain rate in a power-law manner.The rate dependence of the serrated flow has important effects on the dynamics and stability of shear banding process,and leads to an optimal plasticity achieved around the critical strain rate for the disappearance of serrated flow.These results are discussed and interpreted in terms of the mi-croscopic deformation theory and the stick-slip dynamics of shear banding for bulk metallic glasses.     

Advancing and Receding Contact Angles of Tin and Its Alloys on the Surface of a Solidified Glass Mass

The temperature dependence of advancing and receding contact angles has been determined for tin and its alloys with silicon, aluminum, and iron on the surface of a solidified glass mass. The advancing and receding contact angles of melts containing iron differ from those of melts containing silicon and aluminum. The difference becomes more pronounced in the low-temperature range as the iron content in the melt increases.     

六偏磷酸钠对磁性复合流体分散性及光学玻璃抛光性能的影响

为了提高磁性复合流体(Magnetic Compound Fluid,MCF)的抛光性能,通过实验调查无机电解质分散剂六偏磷酸钠(Sodium Hexametaphosphate,SHMP)对MCF颗粒团聚的影响,研究MCF抛光液颗粒分散性与BK7光学玻璃抛光材料去除率和表面粗糙度的变化关系。在MCF中添加不同质量分数的SHMP,测试MCF中颗粒的粒径分布和中值粒径D50的变化,并采用扫描电镜观察MCF中颗粒分散性;利用不同含量SHMP的MCF对BK7光学玻璃进行抛光加工,研究SHMP含量变化对光学玻璃抛光材料去除率和表面粗糙度的影响规律。实验表明,在MCF中添加适量SHMP能够减少抛光液颗粒的团聚,提高MCF抛光液的颗粒分散性,改善BK7光学玻璃的材料去除率和表面质量。当SHMP质量分数为3%时,中值粒径D50达到最小值7.023μm,并且MCF抛光液的分散性最佳,材料去除率达到最大值22.6×10^-4 g/min,表面粗糙度达到最小值15.78 nm。