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使用SPM的纳米级加工技术新进展 总被引:2,自引:0,他引:2
袁哲俊 《纳米技术与精密工程》2004,2(1):45-49
扫描探针显微镜(SPM)现在不仅用于表面微观形貌的检测,同时也用于纳米超精密加工和原子操纵,该文介绍了用STM和AFM进行纳米级加工的各种最新方法:针尖直接雕刻,针尖光刻加工,局部阳极氧化,原子沉积形成纳米点,原子去除形成沟槽微结构,多针尖加工,原子自组装形成三维结构等.使用SPM的纳米级加工对发展微型机械、纳米电子学和微机电系统具有重要意义. 相似文献
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超高密度信息存储研究是纳米电子学的重要研究领域,有机功能薄膜以其独特的性质有可能成为超高密度信息存储介质之一。利用STM研究了N,N-二甲基-N-(3-硝基苯叉)-对苯二胺(DMNBPDA)有机薄膜的存储特性。高分辨扫描电子显微镜的结果表明,在扫描过程中STM对DMNBPDA薄膜表面进行了二次加工,显微Raman谱表明在加工区依然存在着DMNBPDA薄膜,并用原子力显微镜表征了加工区薄膜的表面形貌 相似文献
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采用直流磁控溅射技术在纳米钛表面沉积Mg/TiO_2双层薄膜,研究了Mg中间层对纳米钛表面TiO_2薄膜微结构、动态凝血时间和界面结合力的影响。结果表明,Mg中间层对纳米钛表面TiO_2薄膜微结构、动态凝血时间和界面结合力有显著影响。预制Mg中间层后,纳米钛表面TiO_2薄膜由金红石相(含少量锐钛矿)转变为MgTiO_3、Ti_2O_3和少量金红石相;纳米钛表面TiO_2薄膜沿Mg膜晶界生长成微米级团簇,而团簇内部具有纳米畴特征;纳米钛表面TiO_2薄膜的凝血时间由17 min提高到40 min;纳米钛表面TiO_2薄膜的界面结合力由17N提高到36 N。 相似文献
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采用STM在纳米尺度上对光盘材料结构转变前后表面微观形貌进行了研究,STM结合图象处理和傅利叶分析法可以较好地用于研究薄膜表面形貌的分形特征,用电子束蒸发制备的无定形态记录介质薄膜表面形貌在纳米尺度上呈现出分形特征,经加热晶化后介质薄膜发生结构转变,表面形貌的分形维数增加。 相似文献
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扫描探针显微镜(SPM)由于具有纳米甚至原子量级的分辨率,20多年来已引起各个领域科学家们的广泛兴趣。在精密工程领域,它作为一种极具前途的纳米计量工具,已在许多国家受到了广泛的重视,如美国NIST,德国PTB和英国NPL等都相继开展了基于SPM的纳米计量技术研究。但作为纳米级的计量分析仪器,不仅要有高分辨率,更要有纳米级甚至更高的精度。 相似文献
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采用射频(RF)反应磁控溅射方法制备了具有原子级平滑表面的纳米AlN薄膜。利用傅立叶红外光谱(FTIR)、透射电子显微镜(TEM)、原子力显微镜(AFM)、卢瑟福背散射(RBS)等分析方法对不同实验条件下合成的AlN薄膜进行了表征,研究了不同沉积温度(室温约550℃)下的AlN薄膜的表面形貌特征和结晶特性,探讨了AlN薄膜表面形貌的变化规律及纳米薄膜的形成机制。分析结果显示:不同沉积温度下合成的AlN薄膜均具有原子量级平滑的表面,薄膜表面粗糙度(RMS)为0.2~0.4nm,且不随沉积温度的增加而发生明显变化;薄膜的晶粒尺度为20~30nm,薄膜的折射率随沉积温度的增加而增加。 相似文献
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自组装纳米超薄膜研究进展及其应用 总被引:1,自引:0,他引:1
纳米超薄膜指薄膜厚度处在纳米数量级的薄膜。纳米级超薄膜具有导电、电致发光、光电转换等多种功能,可用于制备传感器、太阳能电池以及光通讯元件,近年来受到广泛重视。自组装是制备多层纳米超薄膜的一种方法,它制备的超薄膜是高度有序和具有方向性的超薄膜。本文就自组装制备纳米超薄膜技术的发展进行了详细的介绍,并对纳米超薄膜的应用发展进行了探讨。 相似文献
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室温下采用射频磁控溅射技术在涤纶纺粘非织造材料表面生长ZnO薄膜。通过扫描电子显微镜及原子力显微镜对ZnO薄膜的微观结构进行表征,用分光光度计测量样品的透光率。结果表明,ZnO薄膜为纳米级,其平均晶粒大小约为30 nm~55 nm。生长了ZnO透明纳米结构的非织造材料对紫外光有较强的吸收能力,在可见光区的透光率达60%以上。 相似文献
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《International journal for numerical methods in engineering》2018,113(9):1488-1506
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method. 相似文献
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Standards are the basis for production enterprises to organize production ex-factory inspection trade 《中国标准化(英文版)》2008,25(1):24-25
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.…… 相似文献
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A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa. 相似文献
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Steffen Müller-Probandt 《材料科学与工程:中英文B版...》2018,(4):161-177
We associate a variety of innovations with the term "Industry 4.0". The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di... 相似文献
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On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.…… 相似文献
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Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß. 相似文献
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Janet Lang 《Materials and Manufacturing Processes》2017,32(7-8):857-866
ABSTRACTThe production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them. 相似文献
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C. Qihong W. Zhan‐Wen J. Yi J. Yehua L. Fei F. Hanguang 《Materialwissenschaft und Werkstofftechnik》2014,45(7):582-590
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill. 相似文献
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Dimiter Hadjistamov 《材料科学与工程:中英文B版...》2019,(2):56-65
The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ... 相似文献