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Friction Characteristics of Nanoscale Sliding Contacts between Multi-Asperity Tips and Textured Surfaces 被引量:3
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作者 TONG Ruiting LIU Geng LIU Tianxiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第6期1109-1117,共9页
Nanoscale sliding contacts of smooth surfaces or between a single asperity and a smooth surface have been widely investigated by molecular dynamics simulations, while there are few studies on the sliding contacts betw... Nanoscale sliding contacts of smooth surfaces or between a single asperity and a smooth surface have been widely investigated by molecular dynamics simulations, while there are few studies on the sliding contacts between two rough surfaces. Actually, the friction of two rough surfaces considering interactions between more asperities should be more realistic. By using multiscale method, friction characteristics of two dimensional nanoscale sliding contacts between rigid multi-asperity tips and elastic textured surfaces are investigated. Four nanoscale textured surfaces with different texture shapes are designed, and six multi-asperity tips composed of cylindrical asperities with different radii are used to slide on the textured surfaces. Friction forces are compared for different tips, and effects of the asperity radii on the friction characteristics are investigated. Average friction forces for all the cases are listed and compared, and effects of texture shapes of the textured surfaces are discussed. The results show that textured surface II has a better structure to reduce friction forces. The multi-asperity tips composed of asperities with R=20r0 (r0=0.227 7 nm) or R=30r0 get higher friction forces compared with other cases, and more atoms of the textured surfaces are taken away by these two tips, which are harmful to reduce friction or wear. For the case of R=10ro, friction forces are also high due to large contact areas, but the sliding processes are stable and few atoms are taken away by the tip. The proposed research considers interactions between more asperities to make the model approach to the real sliding contact problems. The results will help to vary or even control friction characteristics by textured surfaces, or provide references to the design of textured surfaces. 展开更多
关键词 friction characteristics multi-asperity tips textured surfaces nanoscale sliding contacts multiscale method
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Two Dimensional Nanoscale Reciprocating Sliding Contacts of Textured Surfaces 被引量:4
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作者 TONG Ruiting LIU Geng LIU Tianxiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期531-538,共8页
Detailed behaviors of nanoscale textured surfaces during the reciprocating sliding contacts are still unknown although they are widely used in mechanical components to improve tribological characteristics. The current... Detailed behaviors of nanoscale textured surfaces during the reciprocating sliding contacts are still unknown although they are widely used in mechanical components to improve tribological characteristics. The current research of sliding contacts of textured surfaces mainly focuses on the experimental studies, while the cost is too high. Molecular dynamics(MD) simulation is widely used in the studies of nanoscale single-pass sliding contacts, but the CPU cost of MD simulation is also too high to simulate the reciprocating sliding contacts. In this paper, employing multiscale method which couples molecular dynamics simulation and finite element method, two dimensional nanoscale reciprocating sliding contacts of textured surfaces are investigated. Four textured surfaces with different texture shapes are designed, and a rigid cylindrical tip is used to slide on these textured surfaces. For different textured surfaces, average potential energies and average friction forces of the corresponding sliding processes are analyzed. The analyzing results show that "running-in" stages are different for each texture, and steady friction processes are discovered for textured surfaces II, III and IV. Texture shape and sliding direction play important roles in reciprocating sliding contacts, which influence average friction forces greatly. This research can help to design textured surfaces to improve tribological behaviors in nanoscale reciprocating sliding contacts. 展开更多
关键词 nanoscale reciprocating sliding contacts textured surface multiscale method
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Influences of the Textured Surface Micro-Texture Depth on the Friction Coefficient 被引量:2
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作者 Moussa Magara Traore 《World Journal of Mechanics》 2020年第12期221-228,共8页
The use of textured surfaces in lubrication to improve the tribological characteristics has been widely studied. The understanding of the textured surface geometric parameters influences on these tribological characte... The use of textured surfaces in lubrication to improve the tribological characteristics has been widely studied. The understanding of the textured surface geometric parameters influences on these tribological characteristics could help to improve their applications in industry. In this paper, we purpose to analyze the influence of the micro-texture depth on the friction coefficient experimentally. The experiment is conducted using different copper alloy samples have been the first laser textured with different micro-hole depth (40.83 μm and 46.36 μm). A 3D electronic Olympus microscope is used to visualize the shapes of the holes and find the depths. Then, the friction test has been conducted using these samples with the same velocity. The time variation of the friction coefficient is plotted and analyzed. The analysis of time variation of the friction coefficient shows a reduction of friction coefficient with the increase of the micro-hole depth has been observed. In some cases, this reduction is significant. 展开更多
关键词 Friction Coefficient TRIBOLOGY textured surfaces
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Nanoscale Reciprocating Sliding Contacts of Textured Surfaces:Influence of Structure Parameters and Indentation Depth
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作者 Rui-Ting Tong Geng Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第4期168-181,共14页
Textured surfaces are widely used in engineering components as they can improve tribological properties of sliding contacts, while the detailed behaviors of nanoscale reciprocating sliding contacts of textured surface... Textured surfaces are widely used in engineering components as they can improve tribological properties of sliding contacts, while the detailed behaviors of nanoscale reciprocating sliding contacts of textured surfaces are still lack of study. By using multiscale method, two dimensional nanoscale reciprocating sliding contacts of textured surfaces are investigated. The influence of indentation depth, texture shape, texture spacing, and tip radius on the average friction forces and the running-in stages is studied. The results show that the lowest indentation depth can make all the four textured surfaces reach steady state. Surfaces with right-angled trapezoid textures on the right side are better for reducing the running-in stage, and surfaces with right-angled trapezoid textures on the left side are better to reduce wear. Compared with other textured surfaces, the total average friction forces can be reduced by 82.94%–91.49% for the case of the contact between the tip with radius R = 60rand the isosceles trapezoid textured surface. Besides,the total average friction forces increase with the tip radii due to that bigger tip will induce higher contact areas. This research proposes a detailed study on nanoscale reciprocating sliding contacts of textured surfaces, to contribute to design textured surfaces, reduce friction and wear. 展开更多
关键词 NANOSCALE Reciprocating sliding contacts textured surface Structure parameters Indentation depth
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Effect of laser textured surface with different patterns on tribological characteristics of bearing material AISI 52100 被引量:8
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作者 PAUL JOSHUA S DINESH BABU P 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第8期2210-2219,共10页
Chrome steels are used in bearings since they possess high strength and wear resistance.However,when those parts are in service,failure happens due to sliding friction before the lifetime.To improve the durability of ... Chrome steels are used in bearings since they possess high strength and wear resistance.However,when those parts are in service,failure happens due to sliding friction before the lifetime.To improve the durability of the American Iron and Steel Institute(AISI)52100 chromium steel,in this work,the effect of laser surface texturing(LST)was analyzed.With the different patterns of circle and ellipse comparing with the untextured samples,the wear behavior was investigated using the pin-on-disc tribometer.The lubricant used for wear analysis is semisolid lithium grease National Lubricating Grease Institute lubricant(SKF NLGI-3).Sliding wear analysis was conducted at different loads of 10 N,30 N and 50 N for the sliding speed of 750 r/min and 1400 r/min.The wear morphology was analyzed using a scanning electron microscope(SEM).The roughness of the samples was found using a white light interferometer.The effect of different patterns like circle and ellipse,alter the friction and wear properties of chromium alloy was observed compared with the untextured samples.LST shows considerable reduction in friction and wear for ellipsoidal pattern compared with the circular pattern because of wear debris and lubricant getting trapped. 展开更多
关键词 laser surface micro texturing AISI52100 3D surface roughness WEAR scanning electron microscopy
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A mass-conservative average flow model based on finite element method for complex textured surfaces 被引量:9
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作者 XIE Yi LI YongJian +3 位作者 SUO ShuangFu LIU XiangFeng LI JingHao WANG YuMing 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第10期1909-1919,共11页
A mass-conservative average flow model based on the finite element method(FEM) is introduced to predict the performances of textured surfaces applied in mechanical seals or thrust bearings.In this model,the Jakobsson-... A mass-conservative average flow model based on the finite element method(FEM) is introduced to predict the performances of textured surfaces applied in mechanical seals or thrust bearings.In this model,the Jakobsson-Floberg-Olsson(JFO) boundary conditions are applied to the average flow model for ensuring the mass-conservative law.Moreover,the non-uniform triangular grid is utilized,which can deal with the problem of complex geometric shapes.By adopting the modeling techniques,the model proposed here is capable of dealing with complex textured surfaces.The algorithm is proved correct by the numerical experiment.In addition,the model is employed to gain further insight into the influences of the dimples with different shapes and orientations on smooth and rough surfaces on the load-carrying capacity. 展开更多
关键词 mass-conservative average flow model complex textured surfaces JFO boundary conditions finite element method
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Drag reduction characteristics and flow field analysis of textured surface 被引量:6
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作者 Qingshun BAI Jinxuan BAI +2 位作者 Xiangpan MENG Chengcheng JI Yingchun LIANG 《Friction》 CSCD 2016年第2期165-175,共11页
A textured surface with a micro-groove structure exerts a distinct characteristic on drag reduction behavior. The fluid dynamic models of four textured surfaces are constructed in various profile geometries. Computati... A textured surface with a micro-groove structure exerts a distinct characteristic on drag reduction behavior. The fluid dynamic models of four textured surfaces are constructed in various profile geometries. Computational fluid dynamics is used to study the friction factors and drag reduction properties with various flow speeds on the textured surfaces. The friction coefficient varieties in the interface between the fluid and the textured surface are examined according to the simulation of the four geometries with V-shaped, saw tooth, rectangular, and semi-circular sections. The drag reduction efficiencies decrease with the increase in water velocity while it is less than a certain value. Moreover, the simulation results of the velocity, shear stress, energy, and turbulence effect on the V-shaped groove surface are presented in comparison with those of the smooth surface to illustrate the drag reduction mechanism. The results indicate that the peaks of the V-shaped grooves inhibit the lateral movement of the turbulent flow and generate the secondary vortex, which plays a key role in the impeding momentum exchange, thereby decreasing turbulent bursting intensity and reducing shear stress in the near-wall flow field. The kinetic energy and turbulence analysis shows that the vortex in the near-wall flow field on the textured surface is more stable compared to that on the smooth surface. 展开更多
关键词 textured surface drag reduction micro-groove computational fluid dynamics (CFD)
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Modified textured surface MOCVD-ZnO:B transparent conductive layers for thinfilm solar cells 被引量:2
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作者 陈新亮 闫聪博 +4 位作者 耿新华 张德坤 魏长春 赵颖 张晓丹 《Journal of Semiconductors》 EI CAS CSCD 2014年第4期37-41,共5页
Modified textured surface boron-doped ZnO (ZnO:B) transparent conductive layers for thin-film solar cells were fabricated by low-pressure metal organic chemical vapor deposition (LP-MOCVD) on glass substrates. Th... Modified textured surface boron-doped ZnO (ZnO:B) transparent conductive layers for thin-film solar cells were fabricated by low-pressure metal organic chemical vapor deposition (LP-MOCVD) on glass substrates. These modified textured surface ZnO:B thin films included two layers. The first ZnO:B layer, which has a pyramid- shaped texture, was deposited under conventional growth conditions, and the second layer, which has a sphere- like structure, at a relatively lower growth temperature. Typical bi-layer ZnO:B thin films exhibit a high electron mobility of 27.6 cm^2/(V.s) due to improved grain boundary states. For bi-layer ZnO:B, the haze value increases and the total transmittance decreases with the increasing film thickness of the second modification layer. When applied in hydrogenated microcrystalline silicon (μc-Si:H) thin-film solar cells, the modified textured surface ZnO:B layers present relatively higher conversion efficiency than conventional ZnO:B films. 展开更多
关键词 zinc oxide thin films transparent conductive oxides MOCVD textured surface thin-film solar cells
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Generation of Textured Surfaces by Vibration‑Assisted Ball‑End Milling 被引量:1
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作者 Yanjie Yuan Kunkun Yu +2 位作者 Chen Zhang Qi Chen Weixiang Yang 《Nanomanufacturing and Metrology》 EI 2023年第2期90-101,共12页
Textured surfaces have been widely applied in many fields due to their excellent functional performances.Although several micro-scale surface texturing techniques have been used to fabricate surface textures,most are ... Textured surfaces have been widely applied in many fields due to their excellent functional performances.Although several micro-scale surface texturing techniques have been used to fabricate surface textures,most are either very expensive,have material limitations,or lack flexibility.In this study,a novel textured surface generation method using vibration-assisted ball-end milling with a non-resonant vibrator is proposed.Firstly,the configuration of the vibration-assisted ball-end milling system is introduced.Then,the trajectories of the cutting edges are modeled and analyzed.Furthermore,an analysis of a non-resonant vibrator is conducted.Finally,surface texture machining experiments are conducted,and the feasibility of the proposed vibration-assisted ball-end milling method for surface texture fabrication is verified. 展开更多
关键词 Ball-end milling Microdimple Vibration-assisted cutting textured surfaces
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Comparative Studies on Reflection Defect between Textured and Planar Surface Based on TCO Materials
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作者 Alassane Diaw Papa Touty Traore Awa Dieye 《Energy and Power Engineering》 CAS 2022年第10期550-557,共8页
This article presents, on the one hand, the performance of ARC by configurations ITO/Si, MgO/Si, and GeO2/Si. On the other hand, we study the impact of thickness on the reflection of OCTs, because the thickness of OCT... This article presents, on the one hand, the performance of ARC by configurations ITO/Si, MgO/Si, and GeO2/Si. On the other hand, we study the impact of thickness on the reflection of OCTs, because the thickness of OCTs plays an important role on the optical properties and the variation of the reflection and transmission of TCO/Si heterojunctions as a function of thickness is also sown. And the last part of the paper, we will make a comparative study between the performance of silicon textured on the front side and that of silicon where the front side is planar. These two forms of silicon will be covered with ARC. For this, we will use the following materials ITO, MgO, and GeO2 and we represent the variation of the reflection of CAR on a planar surface and on a textured surface as a function of the wavelength. The results show that the reflection is low in textured surface compare to the planar surface. 展开更多
关键词 REFLECTION TCO textured surface
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Experimental Study on Wear Performance and Oil Film Characteristics of Surface Textured Cylinder Liner in Marine Diesel Engine 被引量:6
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作者 Zhi-Wei Guo Cheng-Qing Yuan +1 位作者 Xiu-Qin Bai Xin-Ping Yan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第3期158-167,共10页
It is of a vital importance to reduce the frictional losses in marine diesel engines. Advanced surface textures have provided an e ective solution to friction performance of rubbing pairs due to the rapid development ... It is of a vital importance to reduce the frictional losses in marine diesel engines. Advanced surface textures have provided an e ective solution to friction performance of rubbing pairs due to the rapid development of surface engineering techniques. However,the mechanisms through which textured patterns and texturing methods prove beneficial remains unclear. To address this issue,the tribological system of the cylinder liner?piston ring(CLPR) is investigated in this work. Two types of surface textures(Micro concave,Micro V?groove) are processed on the cylinder specimen using di erent processing methods. Comparative study on the friction coe cients,worn surface texture features and oil film characteristics are performed. The results demonstrate that the processing method of surface texture a ect the performance of the CLPR pairs under the specific testing conditions. In addition the micro V?groove processed by CNCPM is more favorable for improving the wear performances at the low load,while the micro?con?cave processed by CE is more favorable for improving the wear performances at the high load. These findings are in helping to understand the e ect of surface texture on wear performance of CLPR. 展开更多
关键词 Cylinder liner?piston ring(CLPR) surface texture structure Frictional and wear characteristic Oil film characteristic
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Effect of Micro-Dimples on Hydrodynamic Lubrication of Textured Sinusoidal Roughness Surfaces 被引量:1
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作者 Jing-Hu Ji Cai-Wei Guan Yong-Hong Fu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2018年第4期160-167,共8页
Surface texturing has been applied to improving the tribological performance of mechanical components for many years. Currently, the researches simulate the film pressure distribution of textured rough surfaces on the... Surface texturing has been applied to improving the tribological performance of mechanical components for many years. Currently, the researches simulate the film pressure distribution of textured rough surfaces on the basis of the average flow model, and however the influence of roughness on the film pressure distribution could not be precisely expressed. Therefore, in order to study the hydrodynamic lubrication of the rough textured surfaces, sinusoidal waves are employed to characterize untextured surfaces. A deterministic model for hydrodynamic lubrication of microdimple textured rough surfaces is developed to predict the distribution of hydrodynamic pressure. By supplementing with the JFO cavitation boundary, the load carrying capacity of the film produced by micro-dimples and roughness is obtained. And the geometric parameters of textured rough surface are optimized to obtain the maximum hydrodynamic lubrication by specifying an optimization goal of the load carrying capacity. The effect of roughness on the hydrodynamic pressure of surface texture is significant and the load carrying capacity decreases with the increase of the roughness ratio because the roughness greatly suppresses the hydrodynamic effect of dimples. It shows that the roughness ratio of surface may be as small as possible to suppress the effect of hydrodynamic lubrication. Additionally,there are the optimum values of the micro-dimple depth and area density to maximize the load carrying capacity for any given value of the roughness ratio. The proposed approach is capable of accurately reflects the influence of roughness on the hydrodynamic pressure, and developed a deterministic model to investigate the hydrodynamic lubrication of textured surfaces. 展开更多
关键词 Hydrodynamic lubrication surface texturing Micro-dimple Roughness surface Sinusoidal wave
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Laser Surface Textured PTFE Inhibitation for Stick-Slip Phenomenon Under Boundary Lubrication 被引量:1
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作者 LEI Ming WANG Xiaolei HUANG Wei 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2021年第S01期93-101,共9页
When the machine tool is in the start-and stop-stages,the stick-slip phenomenon will be observed and highprecision positioning,machining accuracy and fretting feed will not be guaranteed. The most critical reason is t... When the machine tool is in the start-and stop-stages,the stick-slip phenomenon will be observed and highprecision positioning,machining accuracy and fretting feed will not be guaranteed. The most critical reason is that there is the difference between the dynamic and the static friction coefficients. Textures with different area ratios are fabricated on the surfaces of the upper PTFE-based composite and the friction tests are carried out on a reciprocating tribotester under the boundary lubrication and flat-on-flat contact conditions. The results show that there exists an optimal textured area ratio of 19.6% that can minimize the difference between the dynamic and the static friction coefficients. 展开更多
关键词 machine tool laser surface texturing stick-slip phenomenon difference between the dynamic and static friction coefficients
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Estimation of peak wave period from surface texture motion in videos
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作者 Haipeng Yu Xiaoliang Chu Guang Yuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第9期136-144,共9页
Wave information retrieval from videos captured by a single camera has been increasingly applied in marine observation.However,when the camera observes ocean waves at low grazing angles,the accurate extraction of wave... Wave information retrieval from videos captured by a single camera has been increasingly applied in marine observation.However,when the camera observes ocean waves at low grazing angles,the accurate extraction of wave information from videos will be affected by the interference of the fine ripples on the sea surface.To solve this problem,this study develops a method for estimating peak wave periods from videos captured at low grazing angles.The method extracts the motion of the sea surface texture from the video and obtains the peak wave period via the spectral analysis.The calculation results captured from real-world videos are compared with those obtained from X-band radar inversion and tracking buoy movement,with maximum deviations of 8%and 14%,respectively.The analysis of the results shows that the peak wave period of the method has good stability.In addition,this paper uses a pinhole camera model to convert the displacement of the texture from pixel height to actual height and performs moving average filtering on the displacement of the texture,thus conducting a preliminary exploration of the inversion of significant wave height.This study helps to extend the application of sea surface videos. 展开更多
关键词 low grazing angle sea surface texture VIDEO peak wave period significant wave height image matching
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Development of Texture Mapping Approaches for Additively Manufacturable Surfaces
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作者 Bhupesh Verma Omid Zarei +1 位作者 Song Zhang Johannes Henrich Schleifenbaum 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2022年第4期125-138,共14页
manufacturing(AM)technologies have been recognized for their capability to build complex components and hence have ofered more freedom to designers for a long time.The ability to directly use a computer-aided design(C... manufacturing(AM)technologies have been recognized for their capability to build complex components and hence have ofered more freedom to designers for a long time.The ability to directly use a computer-aided design(CAD)model has allowed for fabricating and realizing complicated components,monolithic design,reducing the number of components in an assembly,decreasing time to market,and adding performance or comfort-enhancing functionalities.One of the features that can be introduced for boosting a component functionality using AM is the inclusion of surface texture on a given component.This inclusion is usually a difcult task as creating a CAD model resolving fne details of a given texture is difcult even using commercial software packages.This paper develops a methodology to include texture directly on the CAD model of a target surface using a patch-based sampling texture synthesis algorithm,which can be manufactured using AM.Input for the texture generation algorithm can be either a physical sample or an image with heightmap information.The heightmap information from a physical sample can be obtained by 3D scanning the sample and using the information from the acquired point cloud.After obtaining the required inputs,the patches are sampled for texture generation according to non-parametric estimation of the local conditional Markov random feld(MRF)density function,which helps avoid mismatched features across the patch boundaries.While generating the texture,a design constraint to ensure AM producibility is considered,which is essential when manufacturing a component using,e.g.,Fused Deposition Melting(FDM)or Laser Powder Bed Fusion(LPBF).The generated texture is then mapped onto the surface using the developed distance and angle preserving mapping algorithms.The implemented algorithms can be used to map the generated texture onto a mathematically defned surface.This paper maps the textures onto fat,curved,and sinusoidal surfaces for illustration.After the texture mapping,a stereolithography(STL)model is generated with the desired texture on the target surface.The generated STL model is printed using FDM technology as a fnal step. 展开更多
关键词 Texture synthesis Design for additive manufacturing Image processing textured surface generation Texture mapping
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Sliding wear characteristics of solid lubricant coating on titanium alloy surface modified by laser texturing and ternary hard coatings 被引量:10
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作者 M.PREM ANANTH R.RAMESH 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第4期839-847,共9页
Titanium alloys are poor in wear resistance and it is not suitable under sliding conditions even with lubrication because ofits severe adhesive wear tendency.The surface modifications through texturing and surface coa... Titanium alloys are poor in wear resistance and it is not suitable under sliding conditions even with lubrication because ofits severe adhesive wear tendency.The surface modifications through texturing and surface coating were used to enhance the surfaceproperties of the titanium alloy substrate.Hard and wear resistant coatings such as TiAlN and AlCrN were applied over texturedtitanium alloy surfaces with chromium as interlayer.To improve the friction and wear resisting performance of hard coatings further,solid lubricant,molybdenum disulphide(MoS2),was deposited on dimples made over hard coatings.Unidirectional sliding weartests were performed with pin on disc contact geometry,to evaluate the tribological performance of coated substrates.The tests wereperformed under three different normal loads for a period of40min at sliding velocity of2m/s.The tribological behaviours ofmulti-layer coatings such as coating structure,friction coefficient and specific wear rate were investigated and analyzed.The lowerfriction coefficient of approximately0.1was found at the early sliding stage,which reduces the material transfer and increases thewear life.Although,the friction coefficient increased to high values after MoS2coating was partially removed,substrate was stillprotected against wear by underlying hard composite layer. 展开更多
关键词 surface texturing chromium interlayer hard coating molybdenum disulphide dry sliding
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Evaluation of surface textures and skid resistance of pervious concrete pavement 被引量:6
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作者 陈瑜 王科进 周文芳 《Journal of Central South University》 SCIE EI CAS 2013年第2期520-527,共8页
Surface textures had long been recognized as primary factors to provide the skid resistance on pavements; however, no measurement of skid resistance on pervious concrete pavement with various surface texture parameter... Surface textures had long been recognized as primary factors to provide the skid resistance on pavements; however, no measurement of skid resistance on pervious concrete pavement with various surface texture parameters had been made. Fractal geometry was introduced in the present work to accurately simulate transect contour curves of pervious concrete specimens through fractal interpolation. It is proved that its fractal dimension (D) can be adopted to measure the skid resistance on pervious concrete pavement, overcoming the shortcomings of both macrotexture depth (DT ) and British portable pendulum number (NBP). Combined with Fujikawa-Koike tire/road contact model, the optimization method of all surface textures was recommended for designing and constructing excellently skid-resistant and noise-absorptive pervious concrete pavement. In addition, evaluating of the abrasion process and attenuation of the surface textures on concrete pavement slabs was also the focus of this work based on accelerated abrasion test. Results show that the surface textures on pervious concrete pavement slabs is extremely durable, compared to those on conventional grooved or exposed aggregate concrete pavement slabs. 展开更多
关键词 pervious concrete surface texture skid resistance fractal dimension ABRASION
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Cooperative effect of surface alloying and laser texturing on tribological performance of lubricated surfaces 被引量:5
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作者 万轶 熊党生 李建亮 《Journal of Central South University》 SCIE EI CAS 2010年第5期906-910,共5页
The cooperative effect of laser surface texturing(LST) and double glow plasma surface alloying on tribological performance of lubricated sliding contacts was investigated.A Nd:YAG laser was used to generate microdimpl... The cooperative effect of laser surface texturing(LST) and double glow plasma surface alloying on tribological performance of lubricated sliding contacts was investigated.A Nd:YAG laser was used to generate microdimples on steel surfaces. Dimples with the diameter of 150μm and the depth of 30-35μm distributed circumferentially on the disc surface.The alloying element Cr was sputtered to the laser texturing steel surface by double glow plasma technique.A deep diffusion layer with a thickness of 30μm and a high hardness of HV900 was formed in this alloy.Tribological experiments of three types of samples(smooth,texturing and texturing+alloying) were conducted with a ring-on-disc tribometer to simulate the face seal.It is found that,in comparison with smooth steel surfaces,the laser texturing samples significantly reduce the friction coefficient.Moreover,the lower wear rate of the sample treated with the two surface techniques is observed. 展开更多
关键词 laser surface texturing double glow plasma surface alloying technology carbon steel tribological performance lubricated surface
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Classification of wood surface texture based on Gauss-MRF Model 被引量:4
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作者 WANG Ke-qi BAI Xue-bing 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期57-61,共5页
The basal theory of Gauss-MRF is expounded and 2-5 order Gauss MRF models are established. Parameters of the 2-5 order Gauss-MRF models for 300 wood samples' surface texture are also estimated by using LMS. The data ... The basal theory of Gauss-MRF is expounded and 2-5 order Gauss MRF models are established. Parameters of the 2-5 order Gauss-MRF models for 300 wood samples' surface texture are also estimated by using LMS. The data analysis shows that: 1) different rexture parameters have a clear scattered distribution, 2) the main direction of texture is the direction represented by the maximum parameter of Gauss-MRF parameters, and 3) for those samples having the same main direction, the finer the texture is, the greater the corresponding parameter is, and the smaller the other parameters are; and the higher the order of Gauss-MRF is, the more clearly the texture is described. On the condition of the second order Gauss MRF model, parameter B1, B2 of tangential texture are smaller than that of radial texture, while B3 and B4 of tangential texture are greater than that of radial texture. According to the value of separated criterion, the parameter of the fifth order Gauss-MRF is used as feature vector for Hamming neural network classification. As a result, the ratio of correctness reaches 88%. 展开更多
关键词 Wood surface texture Gauss-MRF Feature parameter Parameter estimation Separation judgment CLASSIFICATION
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Use of digital image analysis combined with fractal theory to determine particle morphology and surface texture of quartz sands 被引量:4
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作者 Georgia S.Araujo Kátia V.Bicalho Fernando A.Tristao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2017年第6期1131-1139,共9页
The particle morphology and surface texture play a major role in influencing mechanical and hydraulic behaviors of sandy soils. This paper presents the use of digital image analysis combined with fractal theory as a t... The particle morphology and surface texture play a major role in influencing mechanical and hydraulic behaviors of sandy soils. This paper presents the use of digital image analysis combined with fractal theory as a tool to quantify the particle morphology and surface texture of two types of quartz sands widely used in the region of Vitória, Espírito Santo, southeast of Brazil. The two investigated sands are sampled from different locations. The purpose of this paper is to present a simple, straightforward,reliable and reproducible methodology that can identify representative sandy soil texture parameters.The test results of the soil samples of the two sands separated by sieving into six size fractions are presented and discussed. The main advantages of the adopted methodology are its simplicity, reliability of the results, and relatively low cost. The results show that sands from the coastal spit(BS) have a greater degree of roundness and a smoother surface texture than river sands(RS). The values obtained in the test are statistically analyzed, and again it is confirmed that the BS sand has a slightly greater degree of sphericity than that of the RS sand. Moreover, the RS sand with rough surface texture has larger specific surface area values than the similar BS sand, which agree with the obtained roughness fractal dimensions. The consistent experimental results demonstrate that image analysis combined with fractal theory is an accurate and efficient method to quantify the differences in particle morphology and surface texture of quartz sands. 展开更多
关键词 Quartz sands Particle morphology and surface texture Image analysis Fractal theory
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