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The Effect of Interatomic Potentials on the Molecular Dynamics Simulation of Nanometric Machining

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International Journal of Automation and computing 2011年第3期8卷 326-332页

作者： Akinjide Oluwajobi centre for precision Technologies University of Huddersfield

One of the major tasks in a molecular dynamics （MD） simulation is the selection of adequate potential functions, from which forces are derived. If the potentials do not model the behaviour of the atoms correctly, the results produced from the simulation would be useless. Three popular potentials, namely, Lennard-Jones （L J）, Morse, and embedded-atom method （EAM） potentials, were employed to model copper workpiece and diamond tool in nanometric machining. From the simulation results and further analysis, the EAM potential was found to be the most suitable of the three potentials. This is because it best describes the metallic bonding of the copper atoms; it demonstrated the lowest cutting force variation, and the potential energy is most stable for the EAM.

关键词： Interatomic potentials molecular dynamics (MD) nanomachining modelling material removal.

precision Grinding of Reaction Bonded Silicon Carbide Using Coarse Grain Size Diamond Wheels

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Chinese Journal of Mechanical Engineering 2010年第3期23卷 269-275页

作者： ZHAO Qingliang CHEN Junyun BRINKSMEIER E centre for precision Engineering Harbin Institute of Technology Harbin 150001 China Laboratory for precision Machining University of Bremen Bremen D-28359 Germany

Reaction bonded SiC（RBSiC） is attractive for optical application because of its favorable properties and low fabrication cost. However, the difficultness and cost involved in RBSiC grinding limit its application. The investigation on high efficient and low-cost machining with good grinding quality is desired. Generally, high efficient machining for RBSiC is realized by using coarse grain size grinding wheels, but serious grinding damage is inevitable. In this paper, monolayer nickel electroplated coarse grain size diamond grinding wheels with grain sizes of 46 μm, 91 μm, and 151 μm were applied to the grinding of RBSiC. An electrolytic in-process dressing（ELID） assisted conditioning technique was first developed by using cup shape copper bonded conditioning wheels with grain sizes of 15 μm and 91 μm to generate the conditioned coarse grain size wheels with minimized wheel run-out error within 2 μm, constant wheel peripheral envelop as well as top-flattened diamond grains. Then, the grinding experiments on RBSiC were carried out to investigate the grinding performance and material removal mechanism. The experimental results indicate that the developed conditioning technique is applicable and feasible to condition the coarse grain size diamond wheels under optimal conditioning parameters, and the material removal mechanism involved in RBSiC grinding is the combination of brittle fracture and ductile deformation to generate smooth ground surface. This research is significant for the high efficient and low-cost precision grinding of RBSiC with good ground surface quality.

关键词： precision grinding SiC coarse grain size diamond wheel ELID assisted conditioning material removal mechanism

Optimization experiment on eccentric lapping of cylindrical rollers

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Nanotechnology and precision Engineering 2018年第3期1卷 197-204页

作者： Jia Su Julong Yuan Sen Zhang Binghai Lv Ultra-precision Machining Research centre Zhejiang University of Technology

Cylindrical rollers are important elements of bearings,and their machining accuracy and consistency affect the bearing *** a GCr15 cylindrical roller ofФ11×12 as the processing object in this study,the effects of loading pressure,abrasive concentration,and speed combination on cylindrical roller machining precision were investigated using the orthogonal experimental design method on a double-side eccentric pendulum lapping and polishing *** machining parameters of the lapping stage were optimized,and the lapping optimal process parameters were determined by S/N response analysis and analysis of variance(ANOVA).The results show that when the experiment was optimized using loading pressure of 10 N/roller,abrasive concentrationof 20.0 wt%,and rotational speed combination,the material removal rate(MRR)of cylindrical roller reached 0.0896μm/min;the average roughness of the batch decreased from 0.056μm to 0.027μm,51.8%lower than the original batch average roughness,and the deviation decreased from the initial 0.022μm to 0.014μm;the batch average roundness error decreased from 0.47μm to 0.28μm,40.4%lower than the original batch average roundness error,and the deviation decreased from the initial 0.19μm to 0.038μm;and the batch average diameter variation decreased from 4.5μm to about 3.6μm,20%lower than the original batch average diameter *** double-side eccentric lapping of cylinder rollers does not only lead to improvement in the surface quality and shape accuracy of rollers,but also improvement in the batch consistency.

关键词： Cylindrical roller Eccentric pendulum type Orthogonal experiment Lapping Batch consistency

A Simulated Investigation of Ductile Response of GaAs in Single-Point Diamond Turning and Experimental Validation

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Nanomanufacturing and Metrology 2020年第4期3卷 239-250页

作者： Pengfei Fan Fei Ding Xichun Luo Yongda Yan Yanquan Geng Yuzhang Wang centre for precision Manufacturing DMEMUniversity of StrathclydeGlasgowUK Center for precision Engineering Harbin Institute of TechnologyHarbinPeople's Republic of China

In this paper,molecular dynamic(MD)simulation was adopted to study the ductile response of single-crystal GaAs during single-point diamond turning(SPDT).The variations of cutting temperature,coordination number,and cutting forces were revealed through MD *** experiment was also carried out to qualitatively validate MD simulation model from the aspects of normal cutting *** simulation results show that the fundamental reason for ductile response of GaAs during SPDT is phase transition from a perfect zinc blende structure(GaAs-I)to a rock-salt structure(GaAs-II)under high ***,a strong anisotropic machinability of GaAs was also found through MD simulations.

关键词： Molecular dynamic simulation Single-point diamond turning Gallium arsenide Anisotropy Ductile response

Study of nanoscratching of polymers by using molecular dynamics simulations

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Science China(Physics,Mechanics & Astronomy) 2013年第9期56卷 1760-1769页

作者： YUAN DanDan ZHU PengZhe FANG FengZhou QIU Chen State Key Laboratory of precision Measuring Technology and Instruments Centre of MicroNano Manufacturing TechnologyTianjin University

Molecular dynamic simulations are performed to study the nanoscratching behavior of *** effects of scratching depth,scratching velocity and indenter/polymer interaction strength are *** is found that polymer material in the scratching zone around the indenter can be removed in a ductile manner as the local temperature in the scratching zone exceeds glass transition temperature *** recovery of polymer can be more significant when the temperature approaches or exceeds *** tangential force,normal force and friction coefficient increase as the scratching depth increases.A larger scratching velocity leads to more material deformation and higher *** tangential force and normal force are larger for a larger scratching velocity whereas the friction coefficient is almost independent of the scratching velocities *** is also found that stronger indenter/polymer interaction strength results in a larger tangential force and friction coefficient.

关键词： polymer nanoscratching molecular dynamics

Structure and Tribological Property of TiBN Nanocomposite Multilayer Synthesized by Ti-BN Composite Cathode Plasma Immersion Ion Implantation and Deposition

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Chinese Physics Letters 2016年第9期33卷 73-76页

作者：吕文泉王浪平曹永志顾至伟王小峰闫永达于福利 State Key Laboratory of Advanced Welding & Joining Harbin Institute of Technology centre for precision Engineering Harbin Institute of Technology

A Ti-BN complex cathode is made from Ti and h-BN powders by the powder metallurgy technology, and TiBN coating is obtained by plasma immersion ion implantation and deposition with this Ti-BN composite cathode. The TiBN coating shows a self-forming multilayered nanocomposite structure while with relative uniform elemental distributions. High resolution transmission electron microscopy images reveal that the multilayered structure is derived from different grain sizes in the nanocomposite. Due to the existence of h-BN phase, the friction coefficient of the coating is about 0.25.

关键词： of in is BN Structure and Tribological Property of TiBN Nanocomposite Multilayer Synthesized by Ti-BN Composite Cathode Plasma Immersion Ion Implantation and Deposition by Ti

Effect of Media on the Electric Field of a Rhombic Nanostructure Array

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Chinese Physics Letters 2010年第6期27卷 217-220页

作者： ZHU Shao-Li ZHOU Wei precision Engineering and Nanotechnology centre School of Mechanical and Aerospace Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798

Electric field distribution is an important parameter for nanostructure arrays in nanobiosensing appfications. It can influence the sensitivity and the resolution of nanobiosensors. We focus on the effect of media on the electric field distribution of a rhombic silver nanostructure array. The finite-difference time-domain algorithm- based numerical calculation method is used to monitor the electric field distribution of the silver nanostructures when the refractive index of the medium around the nanostructure array is changed. The calculated results show that tuning the refractive index of the medium around silver can have a considerable influence on the electric field distribution in the reflection and transmission directions. This effect can be used to increase the extinction efficiency and to improve the resolution of the spectra for nanobiosensing.

关键词： Electric field Fields Electricity Economic distribution Optical properties Uses Computers Silver

Evaluation of measurement uncertainty of the high-speed variable-slit system based on the Monte Carlo method

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Frontiers of Mechanical Engineering 2020年第4期15卷 517-537页

作者： Yin ZHANG Jianwei WU Kunpeng XING Zhongpu WEN Jiubin TAN centre of Ultra-precision Optoelectronic Instrumentation Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Ultra-precision Intelligent Instrumentation(Harbin Institute of Technology) Ministry of Industry and Information TechnologyHarbin 150080China

This paper presents a dynamic and static error transfer model and uncertainty evaluation method for a high-speed variable-slit system based on a two- dimensional orthogonal double-layer air-floating guide rail structure. The motion accuracy of the scanning blade is affected by both the moving component it is attached to and the moving component of the following blade during high-speed motion. First, an error transfer model of the high-speed variable-slit system is established, and the influence coefficients are calculated for each source of error associated with the accuracy of the blade motion. Then, the maximum range of each error source is determined by simulation and experiment. Finally, the uncertainty of the blade displacement measurement is evaluated using the Monte Carlo method. The proposed model can evaluate the performance of the complex mechanical system and be used to guide the design.

关键词： air-floating guide rail error transfer model driving and following structure dynamic error uncertainty evaluation Monte Carlo method

Sky location of massive black hole binaries in the foreground of Galactic white dwarf binaries

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 97-108页

作者： Pan Guo Hong-Bo Jin Cong-Feng Qiao Yue-Liang Wu The International centre for Theoretical Physics Asia-Pacific University of Chinese Academy of Sciences The School of Physical Sciences University of Chinese Academy of Sciences Institute for Frontiers in Astronomy and Astrophysics Beijing Normal University National Astronomical Observatories Chinese Academy of Sciences Institute of Theoretical Physics Chinese Academy of Sciences

For space-based gravitational wave （GW） detection,the main noise source for massive black hole binaries （MBHBs） is attributed to approximately 10～7double white dwarf binaries in the *** a GW source,the amplitude of the detector response,recorded by a space-based gravitational wave detector,exhibits a modulation effect with a year period when observing the source from various orbital *** the adverse conditions mentioned above,where there is a strong foreground noise and annual modulation in the signals,we employed the wavelet transform and the strong-amplitude relevant orbital position search methods,which allows the weak MBHB sources to achieve higher locating *** detail,for two MBHB sources of lower intensity,the precision of luminosity distance,represented by the ratio ?DL/DLat the 95%confidence level,is enhanced by factors of ～*** angular resolutions,denoted by??s,are enhanced by a factor of ～*** improvements increase the number of detectable GW sources,facilitate multi-messenger follow-up observations and provide constraints on the cosmological constant.

关键词： space-based gravitational wave detection gravitational waves massive black hole binaries