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Mechanism analysis and improved model for stick-slip friction behavior considering stress distribution variation of interface

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Chinese Physics B 2022年第3期31卷 350-363页

作者：韩靖宇丁甲豪吴宏宇阎绍泽 State Key Laboratory of Tribology Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China

Studying the evolution of interface contact state, revealing the “black box” behavior in interface friction and establishing a more accurate friction model are of great significance to improve the prediction accuracy of mechanical system performance. Based on the principle of total reflection, a visual analysis technology of interface contact behavior is proposed. Considering the dynamic variation of stress distribution in interface contact, we analyze the nonlinear characteristics of contact parameters in different stages of stick-slip process using the above-mentioned experimental technology. Then,we find that the tangential stiffness of the interface is not a fixed value during the stick-slip process and the stress distribution variation is one of the important factors affecting the tangential stiffness of interface. Based on the previous experimental results, we present an improved stick-slip friction model, considering the change of tangential stiffness and friction coefficient caused by the stress distribution variation. This improved model can characterize the variation characteristics of contact parameters in different stages of stick-slip process, whose simulation results are in good agreement with the experimental data. This research may be valuable for improving the prediction accuracy of mechanical system performance.

关键词： stress distribution tangential stiffness friction coefficient stick-slip friction model

Advances in friction of aluminium alloy deep drawing

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friction 2024年第3期12卷 396-427页

作者： Yiren GAO Hongxia LI Danyang ZHAO Minjie WANG Xiaobo FAN School of Mechanical Engineering Dalian University of TechnologyDalian 116023China

Broad use of lightweight aluminium alloy parts in automobile manufacturing,aerospace,electronic communication,and rail transit is mainly formed through deep drawing process.Deep drawing friction is a key boundary condition for controlling the forming quality of aluminium alloy parts.However,due to the oxidation and adhesion tendency of aluminium alloys,the tribological situations of aluminium alloy deep drawing(AADD)system is more complicated than those of traditional deep drawing of steel sheets.Therefore,the study of AADD friction is essential for manufacturing high-performance aluminium alloy parts.Herein,aiming to provide a valuable reference for researchers in related fields,a comprehensive review of AADD friction is provided,including friction mechanism,influencing factors,friction measurement,friction model,friction simulation,and lubrication-free friction control.Finally,a brief conclusion and several current challenges were discussed.

关键词： aluminium alloy deep drawing(AADD) influencing factors friction measurement friction model friction control

Rate-, state-, and pressure-dependent friction model based on the elastoplastic theory

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维普期刊数据库

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friction 2020年第4期8卷 768-783页

作者： Shingo OZAKI Takeru MATSUURA Satoru MAEGAWA Division of System Research Yokohama National UniversityTokiwadai 79-5Hodogaya-kuYokohama 240-8501Japan Department of Electrical and Mechanical Engineering Nagoya Institute of TechnologyGokiso-choShowa-kuNagoya 466-8555Japan

Adhesion is one of essences with respect to rubber friction because the magnitude of the friction force is closely related to the magnitude of adhesion on a real contact area. However, the real contact area during sliding depends on the state and history of the contact surface. Therefore, the friction force occasionally exhibits rate-, state-, and pressure dependency. In this study, to rationally describe friction and simulate boundary value problems, a rate-, state-, and pressure-dependent friction model based on the elastoplastic theory was formulated. First, the evolution law for the friction coefficient was prescribed. Next, a nonlinear sliding surface (frictional criterion) was adopted, and several other evolution laws for internal state variables were prescribed. Subsequently, the typical response characteristics of the proposed friction model were demonstrated, and its validity was verified by comparing the obtained results with those of experiments conducted considering the contact surface between a rough rubber hemisphere and smooth acrylic plate.

关键词： adhesion friction model elastoplastic theory contact surface stick-slip

A first order friction model for lubricated sheet metal forming

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Theoretical & Applied Mechanics Letters 2018年第1期8卷 57-61页

作者： Hans B.Lofgren School of Business Engineering and ScienceHalmstad UniversityP.O.Box 823SE-301 18 HalmstadSweden

This paper presents the derivation of a first order friction model for lubricated sheet metal forming.Assuming purely plastic real contacts, Newton's law of viscosity, and a square root behavior of the hydrodynamic coefficient of friction with respect to the hydrodynamic Hersey parameter an analytic model is found. The model predicts the coefficient of friction as a function of the relative pressure, the relative Hersey parameter and the real contact coefficient of friction. Questions about local and global friction are raised in the validation of the model against flat tool sheet experiments. For some flat tool sheet experiments reasonable agreements are obtained assuming a rigid punch pressure distribution. The restricted number of user inputs makes the model useful in early tool design simulations.

关键词： friction model Lubrication Sheet metal forming

An improved LuGre model for calculating static steering torque of rubber tracked chassis

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Defence Technology（防务技术） 2022年第5期18卷 797-810页

作者： Kang Liang Qun-zhang Tu Xin-min Shen Zhong-hang Fang Xuan Yang Yong Zhang Hui-yu Xiang College of Field Engineering Army Engineering University of PLANanjing210007China State Key Laboratory of Intelligent Manufacturing of Advanced Construction Machinery Xuzhou Construction Machinery GroupXuzhou221004China

Tire and rubber track interchangeable chassis combines the advantages of tire and rubber track,which can greatly improve the maneuverability of military construction machinery.However,there is almost no effective calculation model for the real-time static steering torque.When the relative sliding speed is greater than 0.01 m/s,the influence of friction heating can not be ignored.An improved LuGre model is established to calculate the static real-time steering torque of tire and rubber track interchangeable chassis.Firstly,the friction heating model between rubber and ground is established.Combined with the influence of temperature on the dynamic performance of rubber material,the influence of friction heating on the stiffness and friction coefficient of rubber track is analyzed,and the improved LuGre friction model is established.The steering torque of tire and rubber track interchangeable chassis is affected by rubber material properties,steering speed,pavement type,and ambient temperature.Compared with the original Lu Gre model,the improved LuGre model captures the change in friction torque during multiple in-situ turns due to frictional heating.The error with the experimental data is small,which verifies the effectiveness of the improved LuGre model.

关键词： Rubber track Static steering torque friction model Chassis Maneuverability Vehicle

Evaluation of tool wear and cutting performance based on FEM simulation

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Chinese Journal of Aeronautics 2021年第4期34卷 140-152页

作者： Zhenyu SHI Xin LI Ningmin DUAN Qibiao YANG Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong UniversityJinan 250061China School of Mechanical Engineering Shandong UniversityJinan 250061China School of Mechanical Engineering Hubei University of TechnologyWuhan 430000China

An accurate estimation of tool wear morphology can provide the opportunity to investigate the influence of tool wear on cutting performance as well as reduce the overall production cost.However,tool wear prediction is still a very challenging research issue.In this paper,a novel method for simulating the actual chip formation and wear evolution thorough the 3 D finite element model has been carried out.In order to improve the accuracy of simulation results,the influence of worn tool,stress and temperature distribution on wear rate are considered.Then cutting experiment has been conducted by turning AISI1045 with uncoated carbide tools to validate the accuracy of the proposed model.The comparison between experimental and simulation results show good agreement which proves the ability of the proposed model in forecasting the tool wear.The validated finite element model has been further utilized studying how the worn tool affects the cutting performance including actual cutting rake,stress distribution,cutting force and temperature.The results of this paper not only provide a clear understanding of wear evolution between tool rake face and chip,but also are meaningful to optimize tool design and cutting parameters.

关键词： Finite element method friction model Machining Stress distribution Wear

RESEARCH ON THE SELECTION OF friction modelS IN THE FINITE ELEMENT SIMULATION OF WARM EXTRUSION

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Acta Metallurgica Sinica(English Letters) 2003年第2期16卷 90-96页

作者： X.B.Lin H.S.Xiao Z.L.Zhang National Die and Mold CAD Engineering Research Center Shanghai Jiao Tong University1954 Hua Shan RoadShanghai 200030ChinaNational Die and Mold CAD Engineering Research CenterShanghai Jiao Tong University1954 Hua Shan RoadShanghai 200030ChinaNational Die and Mold CAD Engineering Research CenterShanghai Jiao Tong University1954 Hua Shan RoadShanghai 200030China

During the process of finite element simulation of precision warm forging, the selection of friction models has a direct effect on the precision accuracy of finite element simulation results. Among all the factors which influence the selection of friction models, the distribution rule of normal stress at the tool-workpiece interface is a key one. To find out the distribution rule of normal stress at the tool-workpiece interface, this paper has made a systematic research on three typical plastic deformation processes: forward extrusion, backward extrusion, and lateral extrusion by a method of finite element simulation. Then on the base of synthesizing and correcting traditional friction models, a new general friction model which is fit for warm extrusion is developed at last.

关键词： friction model warm extrusion finite element simulation

Tire Grip Performance Simulation and Improving Method Considering the Influence of Tread Pattern Stiffness

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Journal of Donghua University(English Edition) 2016年第6期33卷 939-943页

作者：王国林付晶周海超杨健梁晨 School of Automotive and Traffic Engineering Jiangsu University

The grip performance of radial tires on dry roads was simulated with the software ABAQUS.A sliding-velocity-dependent friction coefficient on the contact behavior at the tire-pavement interface was selected to describe friction phenomenon for tire and road interface.Anti-lock brake system(ABS) process was achieved by controlling the tire angular velocity to obtain the relationship between friction force and slip rate,while the maximum friction forces were used to evaluate tire grip performance.Physical mechanism of tire grip performance was also analyzed through the frictional force generated from the adhesion region and sliding region by considering the contact differences between the longitudinal slip and the lateral slip,and the deformation characteristics of tire pattern were also investigated.In order to improve tire grip performance,carbon fiber material was added to the tread pattern grooves.The results show that carbon fiber has a significant influence on stiffness distribution of tread patterns and friction force vector in the contact zone.Tire grip performance can be improved by controlling the stiffness distribution and deformation direction of the tread pattern.

关键词： tire tire pattern carbon fiber grip performance friction model

Impulse Controller Design of a Harmonic Drive System with friction

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Journal of Southwest Jiaotong University(English Edition) 2010年第3期18卷 238-243页

作者：李刚俊 Electromechanical Engineering Department Chengdu Electromechanical College

A friction model was established for impulse control design in a precision control system. First, the physical characteristics of the impulse in momentum, such as motion and energy, were analyzed and formulated. Then, experimental response to a new pulse with two harmonic expansions was studied. The first harmonic is the main pulse to drive the arm, and the second harmonic has two functions： its first half helps the main pulse eliminate the dead zone, and its second half, a negative pulse, stops the arm motion quickly. Finally, an impulse feedback controller was developed. Comparison between simulation and experiments shows the effectiveness of the proposed controller.

关键词： Impulse control Harmonic drives friction model Precision systems