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International Journal of Digital Earth 2022年第1期15卷 2422-2439页

作者： Zohreh Alijani Julien Meloche Alexander McLaren John Lindsay Alexandre Roy Aaron Berg Department of Geography Environment and GeomaticsUniversity of GuelphGuelphCanada Département de Géomatique Appliquée Université de SherbrookeSherbrookeCanada Département des Sciences de l’Environment Université du Québec à Trois-RivièresTrois-RivièresCanada

surface roughness plays an important role in microwave remote *** the agricultural domain,surface roughness is crucial for soil moisture retrieval methods that use electromagnetic surface scattering or microwave radiative transfer ***,improved characterization of Soil surface roughness(SSR)is of considerable *** this study,three approaches,including a standard pin profiler,a LiDAR point cloud generated from an iPhone 12 Pro,and a Structure from Motion(SfM)photogrammetric point cloud,were applied over 24 surface profiles with different roughness variations to measure surface *** objective of this study was to evaluate the capability of smartphone-based LiDAR technology to measure surface roughness parameters and compare the results of this technique with the more common *** showed that the iPhone LiDAR technology,when point cloud data is captured in a fine-resolution mode,has a significant correlation with SfM photogrammetry(R2=0.70)and a relatively close agreement with pin profiler(R2=0.60).However,this accuracy tends to be greater for random surfaces and rough profiles with row structure *** results of this study confirm that smartphone-based LiDAR can be used as a cost-effective,fast,and time-efficient alternative tool for measuring surface roughness,especially for rough,wide,and inaccessible areas.

关键词： LiDAR surface roughness structure from motion iPhone pin profiler

Design of GH4169 diaphragm for combined improvements of yield strength and surface roughness

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Clean Energy 2023年第1期7卷 53-58页

作者： Qiushi Wang Guangli He Wenjing Zhao Zhihua Han Linlin Wei National Institute of Clean and Low Carbon Energy.Future Science City Changping Dist.Beijing P.R.China

Diaphragm compressors have become the primary source of on-site hydrogen compression for hydrogen fuelling stations around the *** most common hydrogen-compressor-failure mechanism has been identified as diaphragm fracture due to low ten-sile strength and poor surface *** this study,a new type of GH4169 diaphragm with high yield strength and low surface roughness was ***,tensile behaviours and surface properties of the specimens were characterized by using scanning electron microscopy,an electronic universal testing machine and atomic force microscopy,*** evolution of theandphases with temperature has been ***andphases were precipitant-strengthened phases for GH4169 and the volume and size ofandphases increase with ageing *** addition,thephase is the main strengthening phase andis the supportive strengthening *** strength was increased due to the strengthening phases at the cost of *** roughness of the diaphragm could reach an arithmetic average roughness(Ra)of 0.1μm by applying a cooling-assisted polishing *** work improves the reliability and reduces the auxiliary steps and down-time for diaphragm compressors.

关键词： hydrogen diaphragm compressor diaphragm fracture heat treatment surface roughness

surface roughness Effects on Vortex Torque of Air Supported Gyroscope

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Chinese Journal of Aeronautics 2011年第1期24卷 90-95页

作者： LIANG Yingchun LIU Jingshi SUN Yazhou LU Lihua School of Mechatronics Engineering Harbin Institute of Technology Harbin 150001 China

In order to improve the drift precision of air supported gyroscope, effects of surface roughness magnitude and direction on vortex torque of air supported gyroscope are studied. Based on Christensen's rough surface stochastic model and consistency transformation method, Reynolds equation of air supported gyroscope containing surface roughness information is established. Also effects of mathematical models of main machining errors on vortex torque are established. By using finite element method, the Reynolds equation is solved numerically and the vortex torque in the presence of machining errors and surface roughness is calculated. The results show that surface roughness of slit has a significant effect on vortex torque. Transverse surface roughness makes vortex torque greater, while longitudinal surface roughness makes vortex torque smaller. The maximal difference approaches 11.4% during the range analyzed in this article. However surface roughness of journal influences vortex torque insignificantly. The research is of great significance for designing and manufacturing air supported gyroscope and predicting its performance.

关键词： air supported gyroscope surface roughness Christensen’s stochastic model consistency transformation vortex torque

surface roughness and Roundness of Bearing Raceway Machined by Floating Abrasive Polishing and Their Effects on Bearing's Running Noise

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 543-550页

作者： PANG Guibing QI Xuezhi MA Qinyi ZHAO Xiujun WEN Chunsheng XU Wenji PENG Yanping School of Mechanical Engineering and Automation Dalian Polytechnic University Dalian Wazhou Precision Motor & Automobile Bearing Co. ltd School of Mechanical Engineering Dalian University of Technology

As the two most important indexes of bearing raceway, surface roughness and roundness have significant influence on bearing noise. Some researchers have carried out studies in this field, however, reason and extent of the influence of raceway surface geometric characteristics on bearing running noise are not perfectly clear up to now. In this paper, the raceway of 6309 type bearing＇s inner and outer ring is machined by floating abrasive polishing adopting soft abrasive pad. surface roughness parameters, arithmetical mean deviation of the profile Ra, the point height of irregularities Rz, maximum height of the profile Rmax and roundness fof raceways, are measured before and after machining, and the change rules of the measured results are studied. The study results show that the floating abrasive polishing can reduce the surface geometric errors of bearing raceway evidently. The roundness error is reduced by 25%, Rm^x value is reduced by 35.5%, Rz value is reduced by 22% and Ra value is reduced by 5%. By analyzing the change of the geometrical parameters and the shape difference of the raceway before and after machining, it is found that the floating abrasive polishing method can affect the roundness error mainly by modifying the local deviation of the raceway＇s surface profile. Bearings with different raceway surface geometrical parameter value are assembled and the running noise is tested. The test results show that Ra has a little, Rmax and Rz have a measurable, and the roundness error has a significant influence on the running noise. From the viewpoint of controlling bearings＇ running noise, raceway roundness error should be strictly controlled, and for the surface roughness parameters, R,n^x and Rz should be mainly controlled. This paper proposes an effective method to obtain the low noise bearing by machining the raceway with floating abrasive polishing after super finishing.

关键词： surface roughness roundness polishing lapping bearing raceway noise

surface roughness of Various Diamond-Like Carbon Films

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Plasma Science and Technology 2006年第6期8卷 701-707页

作者：刘东平刘艳红陈宝祥 School of Mathematics and Physics Dalian Nationalities UniversityDalian 116600China State Key Laboratory for Material Modification by Laser Ion and Electron BeamsDalian University of TechnologyDalian 116024China

Atomic force microscopy is used to estimate and compare the surface morphology of hydrogenated and hydrogen-free diamond-like carbon （DLC） films. The films were prepared by using DC magnetron sputtering of a graphite target, pulsed cathodic carbon arcs, electron cyclotron resonance （ECR）, plasma source ion implantation and dielectric barrier discharge （DBD）. The difference in the surface structure is presented for each method of deposition. The influences of various discharge parameters on the film surface properties are discussed based upon the experimental results. The coalescence process via the diffusion of adsorbed carbon species is responsible for the formation of hydrogen-free DLC films with rough surfaces. The films with surface roughness at an atomic level can be deposited by energetic ion impacts in a highly ionized carbon plasma. The hydrocarbon species dangling bonds created by atomic hydrogen lead to the uniform growth of at the a-C：H film surfaces of the ECR or DBD plasmas

关键词： atomic force microscopy diamond-like carbon surface roughness

Effect of surface roughness on Lubrication Performance of Bump-Type Gas Foil Bearings

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Journal of Donghua University(English Edition) 2023年第1期40卷 45-58页

作者：许浩杰杨泊莘李正美安琦 School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China

Taking bump-type gas foil bearings as the research object,a deformation model of bump foil and a thin-plate finite element model of top foil were *** solving Reynolds equation and energy equation,the pressure distribution and the temperature distribution of gas films in foil bearings were ***,a numerical method for calculating the lubrication performance of gas foil bearings with considering the surface roughness was *** a specific example,effects of the surface roughness on the bearing lubrication performance were parametrically *** results indicate that rougher journal surface can lead to larger fluctuation of the lubrication performance,while surface roughness of top foil has few effects on the ***,the mean values of performance parameters almost remain constant at different values of surface roughness.

关键词： foil bearing surface roughness lubrication performance numerical simulation parametric study

surface roughness measurements in NFMQL assisted turning of titanium alloys: An optimization approach

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Friction 2017年第2期5卷 155-170页

作者： Munish K.GUPTA P.K.SOOD MED NIT Hamirpur(H.P.)177005 India

The prediction and optimization of surface roughness values remain a critical concern in nano-fluids based minimum quantity lubrication (NFMQL) turning of titanium (grade-2) alloys. Here, we discuss an application of response surface methodology with Box–Cox transformation to determine the optimal cutting parameters for three surface roughness values, i.e., Ra, Rq, and Rz, in turning of titanium alloy under the NFMQL condition. The surface roughness prediction model has been established based on the selected input parameters such as cutting speed, feed rate, approach angle, and different nano-fluids used. Then the multiple regression technique is used to find the relationship between the given responses and input parameter. Further, the experimental data were optimized through the desirability function approach. The findings from the current investigation showed that feed rate is the most effective parameter followed by cutting speed, different nano-fluids, and approach angle on Ra and Rq values, whereas cutting speed is more effective in the case of Rz under NFMQL conditions. Moreover, the predicted results are comparatively near to the experimental values and hence, the established models of RSM using Box-Cox transformation can be used for prediction satisfactorily.

关键词： nano-fluids optimization surface roughness turning titanium alloy

surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural Science:Materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2, FENG Zhijing1 and CHENG Kai3(1. State Key Laboratory of Tribiology, Tsinghua University, Beijing 100084, China 2. Department of Material Sciences, Changchun University of Science and Technology, Changchun 130021, China 3. Faculty of Information and Engineering Systems, City Campus, Leeds LS1 3HE, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China Department of Material Sciences Changchun University of Science and Technology Changchun 130021 China Faculty of Information and Engineering Systems City Campus Leeds LS1 3HE United Kingdom

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.22 nm root mean square (RMS) after 20 min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.

surface roughness of optical quartz substrate by chemical mechanical polishing

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Journal of Semiconductors 2014年第11期35卷 168-172页

作者：段波周建伟刘玉岭孙铭斌张玉峰 Institute of Microelectronics Hebei University of Technology

In order to achieve a high-quality quartz glass substrate and to improve the performance of TiO2 antireflection coating, chemical mechanical polishing （CMP） method was used. During CMP process, some process parameters including pressure, polishing head speed, platen speed, slurry flow rate, polishing time, and slurry temperature were optimized to obtain lower quartz surface roughness. According to the experiment results, when pressure was 0.75 psi, polishing head speed was 65 rpm, platen speed was 60 rpm, slurry flow rate 150 mL/min, slurry temperature 20℃, and polishing time was 60 s, the material removal rate （MRR） was 56.8 nm/min and the surface roughness （Ra） was 1.93 A （the scanned area was 10 × 10 μm^2）. These results were suitable for the industrial production requirements.

关键词： quartz substrate surface roughness removal rate CMP process parameters

surface roughness of Flux Film in Continuous Casting Mold

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Journal of Iron and Steel Research(International) 2004年第6期11卷 10-13页

作者： JIANGMao-fa ZHUChuan-yun HANWen-dian NortheasternUniversity Shenyang110004China CentralIronandSteelResearchInstitute Beijing100081China

The corundum plates with a groove were used to freeze molten flux into solid slice to simulate the flux film formed in continuous casting mold,and thereby to study the formation mechanism of flux film with different surface *** effect of some factors on the surface roughness of flux film,such as reheating rate,cooling rate,flux film thickness and crystallization ratio,was discussed.

关键词： flux film surface roughness cooling rate reheating rate thickness crystallization ratio