TaN／NbN纳米多层膜的力学性能与耐磨性

采用反应溅射在多靶溅射仪上制备了调制周期小于73.2nm的一系列TaN/NbN纳米多层膜和TaN,NbN单层薄膜，并采用透射电子显微镜、显微硬度计和凹坑研磨仪研究了薄膜的微结构、力学性能和耐磨性。结果表明，具有成分周期变化的TaN/NbN纳米多层膜在其调制周期为2.3-17.0nm范围内产生硬度异常升高的超硬效应，最高硬度达到HK51.0GPa；磨损实验表明，TaN/NbN纳米多层膜耐磨性远高于TaN和NbN单层膜，其主要原因是调制结构中大量界面的存在，提高了薄膜的韧性。     

TaN/NbN纳米多层膜的力学性能与耐磨性

采用反应溅射在多靶溅射仪上制备了调制周期小于 73 .2nm的一系列TaN/NbN纳米多层膜和TaN ,NbN单层薄膜 ,并采用透射电子显微镜、显微硬度计和凹坑研磨仪研究了薄膜的微结构、力学性能和耐磨性。结果表明 ,具有成分周期变化的TaN/NbN纳米多层膜在其调制周期为 2 3～ 17 0nm范围内产生硬度异常升高的超硬效应 ,最高硬度达到HK 5 1 0GPa ;磨损实验表明 ,TaN/NbN纳米多层膜耐磨性远高于TaN和NbN单层膜 ,其主要原因是调制结构中大量界面的存在 ,提高了薄膜的韧性。     

Ar/N2气体比例对TaN/NbN纳米多层膜机械性能的影响

采用射频磁控溅射系统,以TaN和NbN作为体材料,制备了一系列TaN/NbN纳米多层膜.通过XRD,纳米力学测试系统分析了该体系合成中Ar/N2气体比例对多层膜结构与机械性能的影响.结果表明,纳米多层膜的硬度值普遍高于两种个体材料混合相的值;当FArFN2=10时TaN的(110)峰加强,TaN的晶体结构以六方结构为主,NbN的晶体结构以面心立方结构为主,此时,多层膜体系的硬度、弹性模量以及膜基结合性能均达到最佳效果(最大硬度为30 GPa),摩擦磨损实验表明,Ar/N2比为101的TaN/NbN多层膜较其他Ar/N2比的多层膜耐磨性更好,不易发生破损,适合实际应用.     

调制周期对TaN/VN纳米多层膜的影响

本研究选择钽和钒的氮化物作为个体层材料,利用射频磁控溅射系统制备TaN、VN及一系列的TaN/VN多层薄膜。通过XRD和纳米力学测试系统分析了该体系合成以后的晶体结构、调制周期对力学性能的影响。结果表明：多层膜的纳米硬度值普遍高于两种个体材料混合相的硬度值;当调制周期为30 nm时TaN/VN多层膜达到最大硬度31 GPa,结晶出现多元化,多层膜体系的硬度、弹性模量以及耐磨性能均达到最佳效果。     

TiN/NbN纳米多层薄膜的交变应力场和超硬效应

为了研究纳米多层薄膜的超硬效应 ,采用反应溅射法制备从 1 4nm至 2 7nm不同调制周期的一系列TiN/NbN纳米多层膜。高分辨电子显微镜对薄膜的调制结构和界面生长方式的观察发现 ,TiN/NbN膜具有很好的调制结构 ,并呈现以面心立方晶体结构穿过调制界面外延生长的多晶超晶格结构特征。显微硬度测量表明 ,TiN/NbN纳米多层膜存在随调制周期变化的超硬效应。薄膜在调制周期为 8 3nm时达到HK39 0GPa的最高硬度。分析认为 ,两种不同晶格常数的晶体外延生长形成的交变应力场 ,对材料有强化作用 ,这是TiN/NbN纳米多层膜产生超硬效应的主要原因     

TiN／NbN纳米多层薄膜的交变应力场和超硬效应

为了研究纳米多层薄膜的超硬效应，采用反应溅射法制备从1.4nm至27nm不同调制周期的一系列TiN/NbN纳米多层膜。高分辨电子显微镜参薄膜的调制结构和界面生长方式的观察发现，TiN/NbN膜具有很好的调制结构，并呈现以面心立方晶体结构穿过调制界面外延生长的多晶超晶格结构特征。显微硬度测量表明，TiN/NbN纳米多层膜存在随调制周期变化的超硬效应。薄膜在调制周期为8.3nm时达到HK39.0 Gpa的最高硬度。分析认为，两种不同晶格常数的晶体外延生长形成的交变应力场，对材料有强化作用，这是TiN/NbN纳米多层膜产生超硬效应的主要原因。     

工作气压对TaN/VN纳米多层膜结构与机械性能的影响

本研究选择钽和钒的氮化物作为个体层材料，利用超高真空射频磁控溅射系统制备TaN、VN及一系列的TaN／VN多层薄膜。通过XRD，纳米力学测试系统分析了该体系合成中工作气压对多层膜结构与机械性能的影响。结果表明：多层膜的纳米硬度值都高于两种个体材料混合相的硬度值；当工作气压为0．2Pa时，结晶出现多元化，多层膜体系的硬度、弹性模量、应力均达到最佳效果，最大硬度达到31GPa。多层膜的机械性能改善明显与工作气压的变化有直接的联系。证明了通过选择合适的工作气压条件，合成具有高硬度的纳米多层膜是可以实现的。     

Si含量对NbN/CrSiN纳米多层膜微观结构和力学性能的影响

采用磁控溅射工艺在Si底片依次沉积NbN、CrSiN纳米层,通过改变靶材的Si含量,制备出一系列NbN/CrSiN纳米多层膜。分别采用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、高透射电子显微镜(HRTEM)和纳米压痕仪研究Si含量对NbN/CrSiN纳米多层膜显微结构和力学性能的影响。实验结果表明,随着Si含量的增加,NbN相的结晶程度先增加后降低,薄膜的硬度和弹性模量也是先增高后降低,在n(Si)∶n(Nb)=3∶22时获得最高硬度和弹性模量,分别为31.92和359.3GPa。显微结构表征表明,当n(Si)∶n(Nb)=3∶22时,NbN/CrSiN纳米多层膜柱状晶生长状况最好,CrSiN层在NbN层的模板作用下转变为面心立方结构,并与NbN层呈共格外延生长。薄膜力学性能的提高主要与CrSiN与NbN形成的共格外延生长结构有关。     

Zr基氮化物／金属Cu纳米多层膜的强韧化研究

多层结构可以提高材料的强度、弹性模量和韧性。当尺寸减小到纳米量级时,性能将产生飞跃变化。首先探讨了多层结构提高强度、弹性模量和韧性等性能的基本原理,然后阐明了纳米尺度效应及理论,重点以过渡族金属氮化物ZrN纳米多层膜为例,研究了氮化物／金属（ZrN／Cu）纳米多层膜、ZrAIN纳米复合膜以及ZrAIN／Cu纳米多层膜的强韧化性能。结果表明,ZrN／Cu纳米多层膜的断裂韧性约是二元ZrN薄膜的2倍。当纳米多层膜的Cu单层厚度为2013131时,多层膜的K1C值最高。ZrAIN复合膜的断裂韧性与Al含量密切相关,当Al原子分数为23％时,薄膜的KIc值达3．17MPa·m^1/2,其硬度〉40Gpa,Al原子分数为47％的薄膜的K1C值则降低到1．13MPa·m…。,其硬度降低至17．1GPa。与z州／cu纳米多层膜和ZrAlN复合膜相比,以ZrAIN层和cu层为调制结构制备的ZrAlN／Cu纳米多层膜具有最高的硬度和最好的韧性。     

调制周期对ReB2/TaN纳米多层膜的结构和力学性能影响

利用射频磁控溅射方法(衬底温度20℃)制备TaN,ReB2单层膜及ReB2/TaN纳米多层膜,并通过XRD,SEM,XP-2表面轮廓仪及纳米力学测试系统对薄膜的微结构和力学性能进行表征,分析调制周期对其影响.结果表明:TaN和ReB2均具有典型的六方结构,在其构成的多层膜中,当调制周期达到8～12nm附近时,纳米多层膜...     

Microstructure and mechanical properties of polycrystalline NbN/TaN superlattice films

The polycrystalline NbN/TaN superlattice films have been grown on the substrates of 18-8 stainless steel by reactive magnetron sputtering. The microstructure and microhardness of the superlattice films have been studied with X-ray diffraction (XRD), high resolution transmission electron microscopy (HREM) and microhardness tester. The results showed that the NbN layers are of face cubic and the TaN layers are hexagonal crystal structure in the NbN/TaN superlattice films. The lattice plane (111) of NbN are coherent with the (110) of TaN and the lattice mismatch is 3.18%. The NbN/TaN superlattice film demonstrated superhardness effects. The maximum Knoop hardness value reached 5100 kgf/mm² with a modulation period from 2.3 nm to 17.0 nm. It was proved that even if NbN layers did not take the same crystal structure as TaN layers, hardness anomalous phenomenon still can be produced as long as the coherent strains exist.     

Cu/Zr纳米多层膜微结构与力学性能

本文利用直流磁控溅射方法在石英玻璃基片上制备一系列自支撑Cu/Zr纳米多层膜,使用箱式电炉对多层膜进行退火处理,利用显微硬度计,X射线衍射仪、扫描探针显微镜表征了多层膜的力学性能与微观结构,研究了不同工艺参数对纳米多层膜性能的影响.研究结果表明:当Cu调制层厚从42 nm增加至140nm时,多层膜显微硬度从4.9 GPa逐渐降低至4.0 GPa;当Zr调制层厚从3.2 nm增加至4.8 nm时,显微硬度值从6.51 GPa降低至5.64 GPa,硬度值降低13.4%,而从4.8 nm增至8 nm时,显微硬度值变化不大(约5.7 GPa);合适的温度退火时,多层膜微观缺陷消失,表面形貌更均匀,显微硬度增加.利用Chu和Barnett提出的硬度增强理论模型对Cu/Zr纳米多层膜表现出的超硬现象进行了理论分析和解释.     

The microstructure and mechanical properties of TaN/TiN and TaWN/TiN superlattice films

The microstructure and the microhardness of the TaN/TiN and TaWN/TiN superlattice films have been studied with X-ray diffraction, transmission electron microscopy and microhardness tester. The results showed that both TaN/TiN and TaWN/TiN superlattice films have a cubic crystal structure with an epitaxially grown mode of polycrystallinity. Lattice constants of superlattice films are between those of the constituent materials. The superhardness effect was found in TaN/TiN and TaWN/TiN superlattice films and the maximum hardness value was 40.0 GPa at a modulation period of 9.0 nm for TaN/TiN, and 50.0 GPa at a modulation period of 5.6 nm for TaWN/TiN. It is proposed that the lattice mismatch affects the microhardness value and the peak position of maximum hardness. The inhibition of dislocation motion by alternating stress fields of interfacial coherent strains is believed responsible for hardness anomalies.     

Structure,hardness and tribological properties of nanolayered TiN/TaN multilayer coatings

TiN/TaN coatings, consisting of alternating nanoscaled TiN and TaN layers, were deposited using magnetron sputtering technology. The structure, hardness, tribological properties and wear mechanism were assessed using X-ray diffraction, microhardness, ball-on-disc testing and a 3-D surface profiler, respectively. The results showed that the TiN/TaN coatings exhibited a good modulation period and a sharp interface between TiN and TaN layers. In mutilayered TiN/TaN coatings, the TiN layers had a cubic structure, but a hexagonal structure emerged among the TaN layers besides the cubic structure as the modulation period went beyond 8.5 nm. The microhardness was affected by the modulation period and a maximum hardness value of 31.5 GPa appeared at a modulation period of 8.5 nm. The coefficient of friction was high and the wear resistance was improved for TiN/TaN coatings compared with a homogenous TiN coating, the wear mechanism exhibited predominantly ploughing, material transfer and local spallation.     

TiN／AIN纳米多层膜的调制周期及力学性能研究

采用一种新型的离子束辅助非平衡反应磁控溅射设备制备了TiN／AlN纳米多层复合膜。采用XRD衍射、TEM、显微硬度计和干涉显微镜对TiN／AlN纳米多层膜的微结构和力学性能进行了表征。结果表明：TiN／AlN多层膜有良好的周期；调制结构影响薄膜的择优取向，薄膜整体表现出硬度增强的效果，硬度随调制周期的变化而变化并在调制周期为7、5nm时达到最大值。     

The effect of annealing on structural, electrical and optical properties of nanostructured ZnS/Ag/ZnS films

In this paper a ZnS/Ag/ZnS (ZAZ) nano-multilayer structure is designed theoretically and optimum thicknesses of ZnS and Ag layers are calculated at 35 and 17 nm, respectively. Several conductive transparent ZAZ nano-multilayer films are deposited on a glass substrate at room temperature by thermal evaporation method. Changes in the electrical, structural, and optical properties of samples are investigated with respect to annealing in air at different temperatures. High-quality nano-multilayer films with the sheet resistance of 8 Ω/sq and the optical transmittance of 83% at 200 °C annealing temperature are obtained. The figure of merit is applied on the ZAZ films and their performance as transparent conductive electrodes are determined.     

Properties of Ultra-Thin NbN Films for Membrane-Type THz HEB

Various buffer layers have been investigated in order to improve the crystalline quality of NbN ultra-thin films. The structural properties, the thickness, the surface morphology of 5–10 nm NbN films have been studied by different techniques. Uncertainty on thickness measurements in this range and the relation between NbN film quality and gain bandwidth are discussed in the framework of their use in Hot Electron Bolometers (HEB).      

TiAlN/VN纳米多层膜的微结构与力学和摩擦学性能

采用反应磁控溅射制备了TiAlN/VN纳米多层膜, 并使用X射线衍射分析(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、纳米压痕仪和多功能摩擦磨损试验机对多层膜的微结构与力学和摩擦学性能进行了表征和分析。研究结果表明: 不同调制周期的TiAlN/VN多层膜均呈典型的柱状晶生长结构, 插入VN层并没有打断TiAlN涂层柱状晶的生长。在一定调制周期下, TiAlN/VN纳米多层膜中的TiAlN和VN层之间能够形成共格生长结构, 其硬度和弹性模量相比于TiAlN单层膜均有显著提升, 其中, TiAlN (10 nm)/VN (10 nm)的硬度和弹性模量最大增量分别达到39.3%和40.9%。TiAlN/VN纳米多层膜的强化主要与其共格界面生长结构有关。另外, TiAlN单层膜的摩擦系数较高(~0.9), 通过周期性地插入摩擦系数较低的VN层能够使得TiAlN的摩擦系数大大降低, TiAlN/VN纳米多层膜的摩擦系数最低为0.4。     

Influence of Ar/N2 Flow Rate on Structure and Property for TaN/NbN Multilayered Coatings

TaN/NbN multilayered coatings with nanoscale bilayer periods were synthesized at different Ar/N2 flow rates by RF （radio frequency） magnetron sputtering. XRD （X-ray diffraction） and Nano Indenter System were employed to investigate the influence of Ar/N2 flow rate （FAr：FN2） on microstructure and mechanical properties of the coatings. The low-angle XRD pattern indicated a well-defined composition modulation and layer structure of the multilayered coating. All multilayered coatings almost revealed higher hardness than the rule-of-mixtures value of monolithic TaN and NbN coatings. At FAr：FN2=10, the multilayered coating possessed desirable hardness, elastic modulus, internal stress, and fracture resistance, compared with ones synthesized at other Ar/N2 flow rates. The layered structure with strong mixture of TaN （110）, （111）, （200） and Nb2N （101）textures should be related to the enhanced mechanical properties.