文摘辑要

电沉积技术在纳米多层薄膜材料制备中的应用对纳米多层膜的研究进行了综述,讨论了单槽法、双槽法电镀纳米多层膜的原理,介绍了纳米多层膜的电沉积机制。总结了近年来人们对研究纳米多层膜所做的工作,分析了纳米多层膜的发展趋势。     

Cu对AlN/TiN-Cu复合多层膜微观结构和力学性能的影响

采用多弧离子镀膜设备制备了掺杂Cu的AlN/TiN-Cu纳米复合多层膜,利用FESEM、HRTEM和XRD分别表征了薄膜的微观结构和相组成,用压入法和划痕法确定了薄膜的硬度和膜/基结合力,研究了Cu对AlN/TiN-Cu复合多层膜微观结构和力学性能的影响。结果表明,Cu的掺杂对薄膜的微观结构有较大的影响。薄膜的平均晶粒尺寸随Cu含量的增加而逐渐减小。掺入少量Cu后,薄膜的硬度均有提高,但不同种类的薄膜有不同的临界载荷变化趋势,纳米复合单层薄膜的临界载荷有所增大,而纳米复合多层膜的临界载荷反而有所减小。     

电镀与环保2008年第5期

电沉积技术在纳米多层薄膜材料制备中的应用对纳米多层膜的研究进行了综述,讨论了单槽法、双槽法电镀纳米多层膜的原理,介绍了纳米多层膜的电沉积机制。总结了近年来人们对研究纳米多层膜所做的工作,分析了纳米多层膜的发展趋势。     

以三维纳米多孔铜膜为集流体锡电极的制备及储锂性能

通过一种新颖的脱合金方法制备厚度为5μm、平均孔径为200~300 nm的三维纳米多孔铜膜,制备过程涉及铜基体上镀锌层的热处理与酸浸过程。以三维纳米多孔铜膜为基体,采用阴极电沉积法制备纳米多孔结构的锡膜电极。应用扫描电子显微镜(SEM)、X线衍射分析(XRD)和恒流充放电方法对所制备的膜电极的结构与电化学性能进行表征。所制备的多孔锡电极在0.1 C率下的首次充放电中的可逆储锂容量为864 mA?h/g,该容量已接近锡的理论容量(993 mA·h/g);在50次充放电循环后,可逆容量仍有541 mA?h/g。纳米多孔结构、纳米尺度的锡颗粒及高电子导电性的三维纳米多孔铜膜基体等因素是多孔锡电极显示较好储锂性能的主要原因。     

碳包覆氧化镍纳米颗粒制备与电化学性能研究

采用直流电弧放电等离子体技术制备了核壳结构碳包覆氧化镍纳米颗粒,并采用X射线衍射、高分辨透射电子显微镜、X射线能量色散分析谱仪和表面物理吸附仪等测试技术对样品的微观结构进行研究。并利用循环伏安法、恒电流充放电以及交流阻抗等技术研究其作为超级电容器电极材料的电化学性能。结果表明:直流电弧等离子体技术制备的碳包覆氧化镍纳米颗粒具有典型的核壳结构,内核为面心立方结构的氧化镍纳米颗粒,外壳为碳层。颗粒形貌主要为立方体结构,粒度均匀,分散性良好,粒径分布在30～70 nm范围,平均粒径为50 nm,外壳碳层的厚度为5 nm。碳包覆氧化镍纳米颗粒具有较高的比容量和良好的电化学活性。     

硼-硫酸-草酸电解液降压阳极氧化疏孔膜层制备及表征

使用铝合金在硼-硫酸-草酸电解液中阳极氧化制备有序多孔层。初步探讨了恒流和降压阳极氧化过程膜层生长机理,采用扫描电镜(SEM)观察膜层微观形貌,结合电化学阻抗和动电位极化曲线研究不同阳极化工艺制备膜层试样在3.5%NaCl溶液中的耐蚀行为。结果表明,采用三段变压方式制备的阳极氧化膜表面孔密度降低,孔壁增厚,孔径为10~13 nm。疏孔膜层的电化学行为表明孔壁及膜层厚度增大能提高试样电荷传递电阻和耐蚀性能。     

电化学脱合金法在FeCrAl纤维毡表面制备纳米自组装结构

为了改善纤维毡对催化剂的粘结强度,降低催化剂中活性组元的用量,采用电化学脱合金法在FeCrAl纤维毡表面制备了连续均匀的纳米多孔结构膜.利用EG&G PAR M273恒电位仪测量动态电势极化曲线和阳极极化曲线,研究了纳米多孔结构的形成机理.结果表明:纳米多孔结构膜形成的临界电压为1.2 V.在此条件下,Al元素和Cr元素被选择溶解,Fe被氧化成纳米结构膜.     

摩擦辅助喷射电沉积纳米晶镍的电化学腐蚀行为

采用摩擦辅助喷射电沉积工艺和传统喷射电沉积工艺制备纳米晶镍,用TEM对比分析了二者的组织结构,用电化学极化法研究了2种纳米晶镍层在3.5%NaCl(质量分数)溶液及1 mol/L H2SO4溶液中的腐蚀行为。结果表明,摩擦辅助喷射电沉积结晶过程更加均匀,制备的纳米晶镍层组织致密,晶粒细小,平均晶粒达到9.77 nm;在2种腐蚀溶液中,摩擦辅助喷射电沉积制备的纳米晶镍的电化学腐蚀性能均优于传统喷射电沉积;在NaCl溶液中,摩擦辅助喷射电沉积所制纳米晶镍在腐蚀过程中有钝化膜产生。并指出晶粒大小与微观缺陷是影响纳米晶镍耐腐蚀性能的2个重要因素     

TA2纯钛酒石酸钠溶液阳极氧化膜层微观形貌对腐蚀性能的影响

选择酒石酸钠环保电解液,用恒电势法在不同浓度条件(1,5,15,30和50 g/L)下制备TA2纯钛阳极氧化膜。采用原子力显微镜分析膜层的微观三维形貌,使用电化学工作站研究试样在3.5%NaCl溶液低电位下的极化曲线和电化学交流阻抗谱,探讨微观三维形貌对耐腐蚀性能的影响。结果表明:15 g/L浓度时,氧化膜层细小均匀,生长完整,粗糙度较低,具有宽广的钝化区,最大的极化电阻值,较小的致钝电流值和自腐蚀电流值,耐腐蚀性能最佳。     

TiAlN/CrN多层膜的组织结构及耐蚀性机理

目的研究Ti AlN/CrN多层膜及Ti AlN、Cr N单一膜层的微观组织和电化学性能区别,分析不同结构薄膜材料的耐腐蚀性影响因素。基于电化学参数、组织结构和腐蚀形貌特征,为开发新型腐蚀性薄膜提供理论依据。方法采用多弧离子镀方法,在316不锈钢基底上先沉积150 nm Cr薄膜作为过渡层,然后交替沉积Cr N薄膜和Ti AlN薄膜,制备单层厚度为10 nm的Ti AlN/CrN多层膜。作为对比,制备单一Ti AlN、CrN薄膜。通过SEM、XRD表征薄膜断面形貌、组织结构,并分析耐蚀机理,结合极化曲线和阻抗谱对三种涂层进行电化学性能分析,最后对涂层进行浸泡腐蚀试验。结果 Ti Al N/Cr N纳米多层膜为面心立方结构,呈现共格外延生长,且呈(200)择优取向。纳米多层膜的动电位极化曲线测量结果与不锈钢基体和单层薄膜相比,其腐蚀电位正移为-0.36 V,腐蚀电流密度降低为0.501μA/cm~2,极化电阻为120 kΩ·cm~2。阻抗谱试验结果表明,相比较于单层膜和基体,Ti Al N/Cr N多层膜的CPE值最低,为29.83×10~(-6)Ω~(-1)·cm~(-2)·sn,n值为0.922,电阻为1.50×1~06Ω·cm~2。腐蚀形貌分析可得出,多层薄膜腐蚀后表面形貌与沉积态涂层形貌最为接近,认为其具有较高的耐腐蚀性。结论纳米层状结构改变了单一薄膜的原始生长模式,抑制了粗大柱状晶的生长,减小了薄膜的固有缺陷、晶粒尺寸,对薄膜的耐蚀性有正面积极的作用。     

Development of pulse-plating technology for the preparation of coatings with varying composition along their thickness: a historical overview

Electrodeposition has long been used for the preparation of coatings consisting either of a single metal or a combination of two or more metals in the form of an alloy. At a certain level of technological development, the demand arose to obtain coatings which can combine the advantageous properties of different metals none of which alone nor any of their mutual alloy combinations can offer the desired properties. This need was the driving force behind the development of electrodeposition methods to produce layered coatings consisting of alternating constituent layers with widely different behaviour. These so-called ‘compositionally graded coatings’ can be compositionally modulated alloys or multilayers. In the present contribution, a historical overview of the development of various pulse-plating methods for the preparation of compositionally graded coatings from a single bath is given. The most common procedure is the use of a repetition of a pulse sequence. This sequence consists of two or more consecutive deposition pulses of different lengths, current densities and/or deposition potentials. As a particular case, the historical development of corrosion-protective electrodeposited multilayers based on the Zn–Fe system and the state of the art of the system is described.     

Electrodeposition of Compositionally Modulated Alloys—An Overview

A new class of materials known as compositionally modulated alloys (CMA) or artificially modulated multilayers has generated an ever-increasing enthusiasm due to their unique properties. This paper reviews the recent developments in the field of electrodeposition techniques for the production of CMA, which offers many advantages over other methods. It also discusses the structure of CMA and their salient properties such as corrosion resistance, magnetic and mechanical properties, which differ to those obtainable in normal metallurgical alloys. Some of their interesting applications are also discussed.     

Co/Pt多层膜的结构和饱和磁化强度

采用离子束溅射技术制备Ｃｏ／Ｐｔ多层膜,用ＲＢＳ、小角ＸＲＤ和断面ＴＥＭ研究了多层膜的周期性调制结构,用ＶＳＭ研究了磁性层Ｃｏ和顺磁性层Ｐｔ的厚度变化对饱和磁化强度的影响。结果表明,多层膜具有良好的周期性层状结构,和设计值一致。样品的饱和磁化强度（Ｍｓ）随Ｃｏ层厚度增加而增大,随Ｐｔ层的厚度增大而减小。当Ｃｏ层和Ｐｔ层的厚度比一定时,样品的饱和磁化强度不受周期数的影响,符合Ｍｓ＝ＭｃｏｔＣｏ／Ｄ模     

Effect of space charge on the polarization hysteresis characteristics of monolithic and compositionally graded ferroelectrics

A non-linear thermodynamic analysis of ferroelectric systems with localized space charges for monolithic and compositionally graded materials is described wherein the electrostatic interlayer interactions are specifically accounted for. The electrostatic coupling is established through the built-in polarization due to the space charges and the intrinsic polarization variations between the ferroelectric layers. The findings show that the polarization hysteresis response of monolithic stress-free barium strontium titanate (BST) ferroelectrics with asymmetrically distributed space charges result in a displacement of the hysteresis loop along the applied electric field axis. In compositionally graded BST multilayers, the hysteresis response is characterized by off-sets along both the polarization and the electric field axes, yet with magnitudes of displacement that are markedly larger than those for monolithic ferroelectrics.     

Microstructure and mechanical properties of polycrystalline-Ag/amorphous-CoZrNb multilayers

Ag/CoZrNb multilayers were prepared by direct current magnetron sputtering. Their microstructure, hardness, elastic modulus and plastic deformation were investigated by X-ray diffraction, high-resolution transmission electron microscopy, X-ray absorption near-edge structure, field emission scanning electron microscopy and nanoindentation technique. The results show that the multilayers have well modulated structure. For all the multilayers, Ag layer is polycrystalline structure, while CoZrNb layer is amorphous structure. With the decrease of modulation periodicity the elastic modulus decreases due to the compliant interface. The polycrystalline Ag layer not only makes the hardness enhanced with the decrease of modulation periodicity, but also restricts the propagation of shear bands and promotes the nucleation of new shear bands, which may be of help for the plasticity enhancement of amorphous CoZrNb layer.     

STRUCTURE AND MAGNETIC PROPERTIES OF Fe/Pd COMPOSITIONALLY MODULATED FILMS

Metal Fe/Pd compositionally modulated films(CMFs) were prepared by vapour depo-sition from two sources onto glass substrate under vacuum.The modulation and crystalstructures of the films were examined by X-ray diffraction.The magnetic properties weredetermined by vibrating sample magnetometer.The Pd layers in the Fe/Pd CMFs areof fcc structure,and the Fe layer structure transits from bcc into amorphous,state withdecreasing thickness of Fe layer.The dependence of specific saturation magnetizationon thickness of Fe layers has also been discussed.     

金属Fe/Pd成分调制膜的结构和磁性研究

用真空双源蒸镀法在玻璃衬底上制得了金属Fe/Pd成分调制膜。用X射线衍射分析了它们的调制特性和晶格结构;用振动样品磁强计进行磁性测量。结果表明:金属Fe/Pd成分调制膜中Pd层为fcc结构;随着Fe层厚度减小,Fe层结构由bcc转变为非晶态。研究了比饱和磁化强度随Fe层厚度的变化规律并探讨了它的机理。     

Dual Bath Electrodeposition of Alternate Multilayer Coatings of Zinc and Nickel Deposits

ZINC electroplating is well established as a sacrificialcoating for the protection of steel substrates.Nevertheless,such coatings deteriorate and areconsumed quickly in severely corrosive environments.Increasing the thickness of pure zinc coating orimproving the passivation methods after plating mayenhance the corrosion resistance,but there are stillproblems during forming and post-deposition weldingprocesses"'.Recently,a new class of coatingsconsisting of a large number of alternate layers h…     

Fabrication of Zn?Ni/Ni?P compositionally modulated multilayer coatings

Zn? Ni/Ni? P compositionally modulated multilayer (CMM) coatings which have a novel three‐dimension (3d) latticed multilayer structure were prepared by dual‐bath technique. The formation of the special 3d latticed structure was investigated. The adhesion and corrosion resistance of the CMM coatings were studied. The results showed that the special 3d latticed multilayer structure, which was different from the structure of traditional CMM coatings, was formed during Ni? P electroless plating. The 3d latticed structure benefited the adhesion and corrosion resistance of the novel CMM coatings. The barrier effect of the 3d latticed structure is enhanced.     

Tb／Co成分调制膜的磁,磁光性能和热稳定性

用直流磁控溅射制备了Ｔｂ／Ｃｏ成分调制膜，膜调制结构的形成与靶的溅射速率和衬底转速密切有关。对不同周期的Ｔｂ／Ｃｏ膜的极向Ｋｅｒｒ膜滞间回线进行了测量，结果表明：当Ｔｂ／Ｃｏ膜的周期较小时，薄膜具有垂直方向的磁各向异性，较大的矫顽力和较大的磁光效应；当Ｔｂ／Ｃｏ膜的周期较大时，上述性能变差。