STM及AFM在材料断裂与疲劳研究中的应用

扫描隧道显微镜（ＳＥＭ）和原子力显微镜（ＡＦＭ）具有原子级的极高分辨率,可在纳米尺度上获得实空间的表面微观三维菜貌,且可定量表征,因此可用来研究材料断裂与疲劳的微观机理。简要介绍ＳＴＭ和ＡＦＭ在该领域的应用及所取得的若干进展。     

TiB2超硬薄膜的合成及性能

采用离子束溅射方法制备了ＴｉＢ２硬质薄膜，ＡＦＭ观察表明薄膜表面非常光谱，ＡＥＳ、ＸＲＤ和ＸＰＳ分析证明薄膜中主要是Ｂ、Ｔｉ比为１．８，六方结构的ＴｉＢ２多晶体、且呈现强烈的（１０１）择优取向，由超显微压痕测量系统测得的加载、卸载曲线计算得到的薄膜的显微硬度比高达４８ＧＰａ     

载锰活性炭纤维(SACF-Mn)的制备及对乙基硫醇吸附性能的研究ⅠSACF-Mn的制备及结构研究

制备了载锰剑麻基活性炭纤维（ＳＡＣＦ－Ｍｎ），并研究了制备条件对ＳＡＣＦ－Ｍｎ的结构及表面形态的影响。研究表明：增大锰溶液的浓度，提高ｐＨ值，高价态的锰离子都有利于ＳＡＣＦ对锰的吸附；锰化合物的阴离子类型，不仅影响ＳＡＣＦ对锰的吸附，而且对载锰后ＳＡＣＦ的表面形态的影响更显著     

载锰活性炭纤维（SACF—Mn）的制备及对乙基硫醇吸附性能的研究：——I SA …

制备了载锰剑麻基活性炭纤维（ＳＡＣＦ－Ｍｎ），并研究了制备条件对ＳＡＣＦ－Ｍｎ的结构及表面形态的影响。研究表明：增大锰溶液的浓度，提高ｐＨ值，高价态的锰离子都有利于ＳＡＣＦ对锰的吸附；锰化合物的阴离子类型，不仅影响ＳＡＣＦ对锰的吸附，而且对载锰后ＳＡＣＦ的表面形态的影响更显著。     

原子力显微镜

1　引　　言1986年 ,为了观察绝缘材料表面的原子图像 ,ＩＢＭ的Ｇ .Ｂｉｎｎｉｎｇ和斯坦福大学的Ｃ .Ｆ .Ｑｕａｔｅ、Ｃ .Ｇｅｒｂｅｒ合作 ,发明了原子力显微镜 (ＡｔｏｍｉｃＦｏｒｃｅＭｉｃｒｏｓｃｏｐｅ :ＡＦＭ )。当时 ,ＡＦＭ的横向分辨率达到2ｎｍ ,纵向分辨率达到 0 .0 1ｎｍ ,放大倍数高达 10 0万倍以上 ,而且ＡＦＭ对工作环境和样品制备的要求比电镜的低得多 ,因此立即得到了广泛的重视。最早的ＡＦＭ主要是作为观察样品表面形貌的显微镜使用的。由于表面的高低起伏状态能够准确地以数值的形式获取 ,ＡＦＭ也作为检查表面粗…     

用SEM和XRD研究改性活性炭纤维的结构

比较了以ＦｅＳＯ４改性ＡＣＦ其表面形态及微晶结构的变化。经过改性，ＡＣＦ表面形态发生了很大变化—表面被刻蚀，表面孔形态发生变化，ＡＣＦ的石墨微晶尺寸大大减小，出现明显的细晶化趋势。ＳＥＭ和ＸＲＤ两种测试方法的结果基本吻合，在此基础上提出改性模型     

用SEMT和XRD研究改性活性炭纤维的结构

比较了以ＦｅＳＯ４改性ＡＣＦ其表面形态及微晶结构的变化。经过改性，ＡＣＦ表面形态发生了很在大变化－表面被刻蚀，表面孔形态发生变化，ＡＣＦ的石墨微晶尺寸大大减小，出现明显的细晶化趋势。ＳＥＭ和ＸＲＤ两种测试方法的结果基本吻合，在此基础上提出改性模型。     

最新分析方法缩略语

最新分析方法缩略语ＡＦＭ－ＡｔｏｍｉｃＦｏｒｃｅＭｉｃｒｏｓｃｏｐｅ原子力显微镜ＡＭ－ＡｃｏｕｓｔｉｃＭｉｃｒｏｓｃｏｐｙ声学显微术ＥＳ－ＥｍｉｓｓｉｏｎＳｐｅｃｔｒｏｓｃｏｐｙ发射光谱术ＥＳＣＡ－ＥｌｅｃｔｒｏｎＳｐｅｃｔｒｏｓｃｏｐｙｆｏｒＣｈａ...     

最新分析方法缩略语EI

最新分析方法缩略语ＡＦＭ－ＡｔｏｍｉｃＦｏｒｃｅＭｉｃｒｏｓｃｏｐｅ原子力显微镜ＡＭ－ＡｃｏｕｓｔｉｃＭｉｃｒｏｓｃｏｐｙ声学显微术ＥＳ－ＥｍｉｓｓｉｏｎＳｐｅｃｔｒｏｓｃｏｐｙ发射光谱术ＥＳＣＡ－ＥｌｅｃｔｒｏｎＳｐｅｃｔｒｏｓｃｏｐｙｆｏｒＣｈａ...     

PAN氧化纤维增强C／C复合材料的进展

ＰＡＮ氧化纤维增强Ｃ／Ｃ复合材料的进展ＯＰＢａｈｌｅｔａｌ一、简介本文旨在研究不同表面能的ＰＡＮＯＦ增强煤焦油沥青制造复合材料的可行性。这里说明一点，最近Ｍａｒｋｏｖｉｃｅｔａｌ曾试图研制以ＰＡＮＯＦ（空气中处理至２５０－３００℃）为增强材料、以酚醛...     

Augmented reality user interface for an atomic force microscope-based nanorobotic system

A real-time augmented reality (AR) user interface for nanoscale interaction and manipulation applications using an atomic force microscope (AFM) is presented. Nanoscale three-dimensional (3-D) topography and force information sensed by an AFM probe are fed back to a user through a simulated AR system. The sample surface is modeled with a B-spline-based geometry model, upon which a collision detection algorithm determines whether and how the spherical AFM tip penetrates the surface. Based on these results, the induced surface deformations are simulated using continuum micro/nanoforce and Maugis-Dugdale elastic contact mechanics models, and 3-D decoupled force feedback information is obtained in real time. The simulated information is then blended in real time with the force measurements of the AFM in an AR human machine interface, comprising a computer graphics environment and a haptic interface. Accuracy, usability, and reliability of the proposed AR user interface is tested by experiments for three tasks: positioning the AFM probe tip close to a surface, just in contact with a surface, or below a surface by elastically indenting. Results of these tests showed the performance of the proposed user interface. This user interface would be critical for many nanorobotic applications in biotechnology, nanodevice prototyping, and nanotechnology education.     

Teleoperated 3-D Force Feedback From the Nanoscale With an Atomic Force Microscope

In this study, 3-D experimental teleoperated force feedback during contact with nanoscale surfaces is demonstrated using an atomic force microscope (AFM) on the slave side and a haptic device on the master side. To achieve 3-D force feedback, coupling between one of the horizontal forces and the vertical force is a crucial bottleneck. To solve this coupling issue, a novel force decoupling algorithm is proposed. This algorithm uses local surface slopes, an empirical friction force model, and the haptic device motion angle projected onto the surface to estimate the friction value during experiments. With this estimation, it is possible to decouple the three orthogonal forces acting on the tip of the AFM cantilever. Moreover, using an adaptive observer, parameters of the friction model can be changed online, removing the necessity to calibrate the friction model initially. Finally, a modified passivity-based bilateral control is used to reflect the scaled nanoscale forces to the master side and the operator. The performance of the system is demonstrated on experimental results for flat and non-flat, and hard and soft surfaces.      

基于原子力显微镜技术的沥青与矿料表面粗糙度及黏附特性

采用原子力显微镜技术(AFM)的轻敲和力曲线模式,在微观尺度下对沥青与矿料表面的二维图像和三维形貌信息进行采集和分析,并测试和计算表征材料物理黏结特性的表面能。测试和分析结果显示,不同油源的沥青具有明显不同的化学组分和表面粗糙度,具有蜂形结构的沥青表面粗糙度更大。老化将明显减少沥青的表面粗糙度,降低其表面能,进而对沥青与矿料的黏附产生不利影响。结合宏观的黏附拉拔力学试验,对沥青和矿料表面粗糙度、表面能与宏观拉拔强度间的关联进行统计分析。结果表明,对于含蜂形结构的沥青,沥青和矿料表面粗糙度对黏附力学性能较为重要;而对于不含蜂形结构的沥青,其与矿料的黏附性更决定于所选材料的表面能,即两种材料间的物理黏结作用。     

具有实时视觉/触觉反馈的纳米操作系统

由于缺乏实时的传感器信息反馈,导致传统的基于原子力显微镜的纳米操作盲目,操作效率和成功率都非常低.为了克服这一问题,设计和实现了一种具有实时视觉和三维触觉反馈的纳米操作系统.当利用该系统进行纳米操作时,操作者不但可以实时感受到探针与被操作物体间的相互作用力,还可以在3D增强现实图像界面中观察到纳米操作场景的变化,并可以在线控制探针的三维运动.这种交互式的操作系统使得纳米操作变得容易可行.纳米刻画实验和多壁碳纳米管的推动实验验证了该系统的有效性和高效率.     

Evaluation of surface characteristics of dental composites using profilometry,scanning electron,atomic force microscopy and gloss-meter

The aim of this in vitro investigation was to compare various roughness and topography measurement methods to characterize the surface quality in several types of resin composites. The initial surface quality of several resin composites was compared. The materials evaluated were of three categories: i) hybrid: TPH Spectrum; ii) reinforced microfill: Micronew and iii) microhybrid: Synergy Duo, Esthet-X, Point.4 and Palfique Estelite. Three Groups of identical disk-shaped specimens (10 × 1.5 mm) were prepared from each material (n = 6) and polished with Soflex discs. Macro-roughness (Ra) was measured with Group 1 by 2-D profilometry. Atomic Force Microscopy (AFM) gave 3-D images and micro-roughness (Ra) of Group 2. Surface optical gloss at 60^∘ was determined for Group 3. Specimens of each material were also studied by scanning electron microscopy. Macro-Ra values (μm) ranged from 0.30 to 0.56. Micro-Ra values ranged from 0.03 to 0.14 and they differed from macro-Ra values in ranking order. Percentage Gloss values ranged from 30.6 to 70.1%. The results revealed that micro-roughness showed a high correlation with gloss values (r = 0.93), whilst macro-roughness did not (r = 0.62). Moreover, the AFM method showed higher capability to distinguish surface roughness compared with the 2-D profilometry and to reveal more detailed definition of surface texture than the examination under SEM.     

GISAXS studies of self-assembling of colloidal Co nanoparticles

In this work we report on the formation of ordered monolayers (2-D) and arrays of rods (3-D) of magnetic Co nanoparticles in magnetic field perpendicular to the substrate surface. Samples were prepared by drying a droplet of colloidal solution of Co nanoparticles (10 nm diameter) on Si/Si₃N₄ substrates in magnetic field between 0.2 and 0.9 T. The samples were characterized by high resolution scanning electron microscopy (SEM), atomic and magnetic force microscopy (AFM/MFM) and grazing incidence small angle X-ray scattering (GISAXS). SEM studies of monolayers show well-ordered 2-D arrays with hexagonal symmetry of 200 nm × 500 nm in size forming a mosaic structure. Rods, about 500 nm in diameter, aligned with the field direction and forming a hexagonal pattern were obtained when higher concentration of colloid and low evaporation rate of the solvent were used. The ordering of nanoparticles in the monolayer analyzed by GISAXS is described by the local order with hexagonal symmetry. The model of close packing of hard spheres is used for ordering of particles inside the rods. Magnetic features corresponding to the 3-D arrays have been observed by MFM pointing out that all magnetic moments in the rod are oriented along the field direction.     

A 2-D model that accounts for 3-D fringing in MEMS devices

MEMS devices such as comb drives and rotary drives are geometrically simple in that each of the components may be represented as a ‘sweep’ of a 2-D cross-section through a given height. This simplicity leads to simpler CAD requirements, geometric robustness, faster visualization, etc. Further, 3-D electrostatic simulation may be simplified to a 2-D problem over the cross-section if one neglects 3-D fringing. Such 2-D simulations provide a quick feedback to the designer on various parameters such as capacitance and electrostatic forces.However, as is well known, 3-D simulations cannot be avoided if fringing is significant, or when these devices need to be fully optimized. Such 3-D simulations unfortunately involve constructing the full 3-D geometry, volume/surface mesh, etc.In this paper, we demonstrate that one can pose and solve a 2-D problem that accounts for 3-D fringing. The proposed technique does not require the construction of the 3-D CAD model or surface/volume mesh. Instead, the 3-D electrostatics problem is collapsed to 2-D via a novel dimensional reduction method. Once the 2-D problem is solved, the full 3-D field and associated charges/forces can be recovered, as a post-processing step. The simplicity and computational efficiency of the technique lends itself well to parametric study and design optimization.     

网格投影式立体视觉三维表面重建系统

提出了一种基于立体视觉的三维表面重建的新方法。该方法以立体视觉为基础,结合网格投影,把被动的立体视觉与主动的非结构光网格投影相结合,采用一种算法简单的由粗到精网格图像立体匹配方法,有效地解决了常用的立体视觉系统中存在的算法复杂、处理时间长、容易产生误匹配等问题。基于该方法的三维表面重建系统具有结构简单、操作方便、数据采集速度快、实时性强等优点。实验结果表明该系统能够有效地对三维表面,特别是对无明显特征的光滑自由三维曲面进行重建。     

Numerical simulation bistatic scattering from three-dimensional conducting rough surface with forward?backward method-based vector basic functions

To more really simulate distribution of vector-induced currents along a three-dimensional (3-D) conducting rough surface, it is better for vector basic functions to be used to describe the vector-induced currents. The forward-backward method (FBM) has been further developed to be combined with the vector basic functions to numerically calculate 3-D conducting rough surface scattering problem in this paper, meanwhile, the FBM is first well explained through some matrix forms. The FBM has been used to numerically simulate the bistatic scattering from 3-D conducting rough surface. Some numerical results have been discussed in the paper.     

碳纤维三维织物脉冲式阳极氧化均匀处理研究

采用阳极氧化法对碳纤维三维织物中的纤维进行表面改性处理，通过三维织物复合材料界面剪切强度 、浸润性能和三维织物中不同部位纤维表面的XPS分析，研究了阳极氧化处理方式对三维织物处理均匀性的影响。实验结果表明，脉冲式处理方法有利于减小处理过程中织物中存在的浓差极化，使三维织物得到均匀处理，从而使复合材料的整体性能得到提高。