scholarly journals A FRACTURE-INDUCED ADHESIVE WEAR CRITERION AND ITS APPLICATION TO THE SIMULATION OF WEAR PROCESS OF THE POINT CONTACTS UNDER MIXED LUBRICATION CONDITION

2021 ◽  
Vol 19 (1) ◽  
pp. 023
Author(s):  
Hui Cao ◽  
Yu Tian ◽  
Yonggang Meng
Keyword(s):  
Adhesive Wear ◽  
Wear Particle ◽  
Rolling Motion ◽  
Morphology Evolution ◽  
Point Contacts ◽  
Wear Process ◽  
Subsurface Layers ◽  
Lubrication Condition ◽  
Simulation Results ◽  
Almost All

Adhesive wear is one of the four major wear mechanisms and very common in almost all macro-, micro- or nanotribosystems. In an adhesive wear process, tiny material fragments are pulled off from one sliding surface and adhered onto the counterpart. Later these fragments form loose particles or transfer between the contact surfaces. Because of the topographical and physicochemical property non-uniformity of engineering surfaces, adhesive wear happens heterogeneously on the loaded sliding surfaces, and it is also discontinuous during sliding or rolling motion owing to the damage accumulation and fracture occurred inside the subsurface layers. Taking account of these characteristics, a novel fracture-induced adhesive wear criterion has been proposed in this study in order to predict local wear of material in sliding. Moreover, the proposed wear criterion is applied to predicting wear particle formation and morphology evolution of mixed lubricated rough surfaces during reciprocating sliding, and the simulation results are compared with the ball-on-disk experimental measurements.

scholarly journals Friction and adhesive wear behavior caused by periodic impact in mixed-lubricated point contacts

2020 ◽  
Vol 12 (2) ◽  
pp. 168781402090166
Author(s):  
Xin Pei ◽  
Wei Pu ◽  
Jialong Yang ◽  
Ying Zhang
Keyword(s):  
Friction Coefficient ◽  
Adhesive Wear ◽  
Wear Behavior ◽  
Critical Role ◽  
Surface Velocity ◽  
Asperity Contact ◽  
Impact Action ◽  
Wear Process ◽  
Lubrication Condition ◽  
Functional Components

Periodic impact is a common phenomenon experienced by functional components. The mechanisms governing the adhesive wear growth caused by the periodic impact are not well understood, which limits the development of antiwear and lubricating behavior. In this work, the periodic impact action caused by rubbing surface velocity and contact load is studied in the sliding wear process under mixed lubrication condition. At each wear simulation circle, the material removal at each asperity contact location is evaluated and the surface topography is renewed correspondingly. The evolutions of friction and wear track are revealed during wear process. We find that the friction coefficient changes periodically caused by the periodic speed, and the wear rate increases almost linearly with either speed period or speed amplitude. The load impact results in an abrupt variation in friction coefficient, while it appears to be limited in adhesive wear state compared to speed, highlighting the critical role of velocity impact in wear formation.

scholarly journals Simulation and Experimental Study on Wear of U-Shaped Rings of Power Connection Fittings under Strong Wind Environment

Materials ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 735
Author(s):  
Songchen Wang ◽  
Xianchen Yang ◽  
Xinmei Li ◽  
Cheng Chai ◽  
Gen Wang ◽  
...  
Keyword(s):  
Abrasive Wear ◽  
Adhesive Wear ◽  
Surface Hardness ◽  
Wear Depth ◽  
Strong Wind ◽  
Wear Model ◽  
Wind Environment ◽  
Simulation Results ◽  
Oxidation Wear ◽  
Good Agreement

The objective of this study was to investigate the wear characteristics of the U-shaped rings of power connection fittings, and to construct a wear failure prediction model of U-shaped rings in strong wind environments. First, the wear evolution and failure mechanism of U-shaped rings with different wear loads were studied by using a swinging wear tester. Then, based on the Archard wear model, the U-shaped ring wear was dynamically simulated in ABAQUS, via the Umeshmotion subroutine. The results indicated that the wear load has an important effect on the wear of the U-shaped ring. As the wear load increases, the surface hardness decreases, while plastic deformation layers increase. Furthermore, the wear mechanism transforms from adhesive wear, slight abrasive wear, and slight oxidation wear, to serious adhesive wear, abrasive wear, and oxidation wear with the increase of wear load. As plastic flow progresses, the dislocation density in ferrite increases, leading to dislocation plugs and cementite fractures. The simulation results of wear depth were in good agreement with the test value of, with an error of 1.56%.

Adhesive Wear Based on Accurate FEA Study of Asperity Contact and n-Point Asperity Model

2016 ◽  
Vol 4 (1) ◽  
pp. 1-24
Author(s):  
Ajay K. Waghmare ◽  
Prasanta Sahoo
Keyword(s):  
Adhesive Wear ◽  
Complete Solution ◽  
Wear Particle ◽  
Wear Volume ◽  
Asperity Contact ◽  
Wear Model ◽  
Element Analysis ◽  
Particle Generation ◽  
Elastic Plastic ◽  
Asperity Model

The paper describes a theoretical study of adhesive wear based on accurate finite element analysis (FEA) of elastic-plastic contact of single asperity and n-point asperity model. The wear model developed considers wear particle generation in whole range of deformation, ranging from fully elastic through elastic-plastic to fully plastic. Well defined adhesion index and plasticity index are used to study the prospective situations arising out of variation in load, material properties, and surface roughness. It is observed that the wear volume at particular level of separation increases with increase in plastic deformation and adhesion effect. Materials having higher tendency to adhesion show higher wear rate. Trend of the results obtained is found in line with the existing solutions which are modeled with conventional asperity concept. Inclusion of separate formulations for intermediate state of deformation of asperities which are based on accurate FEA study gives complete solution.

scholarly journals Effects of Multi-Point Contacts during Object Contour Scanning Using a Biologically-Inspired Tactile Sensor

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 2077 ◽  
Author(s):  
Lukas Merker ◽  
Sebastian J. Fischer Calderon ◽  
Moritz Scharff ◽  
Jorge H. Alencastre Miranda ◽  
Carsten Behn
Keyword(s):  
Steel Wire ◽  
Sense Organ ◽  
Tactile Sensor ◽  
Spring Steel ◽  
Point Contacts ◽  
Contact Points ◽  
Discrete Contact ◽  
Almost All ◽  
Rats And Mice ◽  
Support Reactions

Vibrissae are an important tactile sense organ of many mammals, in particular rodents like rats and mice. For instance, these animals use them in order to detect different object features, e.g., object-distances and -shapes. In engineering, vibrissae have long been established as a natural paragon for developing tactile sensors. So far, having object shape scanning and reconstruction in mind, almost all mechanical vibrissa models are restricted to contact scenarios with a single discrete contact force. Here, we deal with the effect of multi-point contacts in a specific scanning scenario, where an artificial vibrissa is swept along partly concave object contours. The vibrissa is modeled as a cylindrical, one-sided clamped Euler-Bernoulli bending rod undergoing large deflections. The elasticae and the support reactions during scanning are theoretically calculated and measured in experiments, using a spring steel wire, attached to a force/torque-sensor. The experiments validate the simulation results and show that the assumption of a quasi-static scanning displacement is a satisfying approach. Beyond single- and two-point contacts, a distinction is made between tip and tangential contacts. It is shown that, in theory, these contact phases can be identified solely based on the support reactions, what is new in literature. In this way, multipoint contacts are reliably detected and filtered in order to discard incorrectly reconstructed contact points.

scholarly journals The generation mechanism and morphological characterization of cutting debris based on the finite element method

2018 ◽  
Vol 233 (1) ◽  
pp. 205-213 ◽  
Author(s):  
Shuo Wang ◽  
Tonghai Wu ◽  
Jun Cheng ◽  
Yu Han ◽  
Ting Yao
Keyword(s):  
Wear Debris ◽  
Shear Failure ◽  
Normal Load ◽  
Wear Particle ◽  
Generation Mechanism ◽  
Critical Conditions ◽  
Three Dimensional Model ◽  
Micro Cutting ◽  
Deformation And Failure ◽  
Wear Process

Micro-cutting is a material removal mechanism with cutting debris generation, where the condition monitoring of the mechanism is important in a wear process. As a useful technique, wear debris analysis has been widely adopted for identifying the wear mechanisms in a running machine. However, there is no corresponding relationship between wear particle features and wear conditions. This paper investigates the generation mechanism of cutting debris by simulating a micro-cutting process. In particular, this study is to establish a quantitative relationship between their morphologies and cutting conditions. A three-dimensional model with a rigid pyramid sliding on the surface of #45 steel has been developed. The deformation and failure criteria of the steel are the Johnson–Cook and shear failure model, respectively. The conditions for producing cutting wear debris are studied and then the morphological features of wear debris are extracted. The main findings are as follows: (1) the critical conditions for cutting wear particle generation is jointly determined by the attacking angle and the cutting depth; (2) the width and curvature of cutting wear debris are mainly correlated with the normal load, which determines the indentation depth of the pyramid; (3) the curvature of cutting wear debris depends mainly on the sliding velocity. The understanding of the relationship between the cutting wear conditions and the morphologies of wear debris is useful for supporting debris-based wear monitoring.

Numerical Prediction of Surface Wear and Roughness Parameters During Running-In for Line Contacts Under Mixed Lubrication

2018 ◽  
Vol 140 (6) ◽  
Author(s):  
Yazhao Zhang ◽  
Alexander Kovalev ◽  
Noriyuki Hayashi ◽  
Kensuke Nishiura ◽  
Yonggang Meng
Keyword(s):  
Friction Coefficient ◽  
Contact Region ◽  
Mixed Lubrication ◽  
Asperity Contact ◽  
Wear Particles ◽  
Wear Model ◽  
Wear Process ◽  
Line Contacts ◽  
Lubrication Condition ◽  
Initial Line

A stochastic model for predicting the evolutions of wear profile and surface height probability density function (PDF) of initial line contacts during running-in under mixed lubrication condition is presented. A numerical approach was developed on the basis of stochastic solution of mixed lubrication, which combined the Patir and Cheng's average flow model for calculation of the hydrodynamic pressure and the Kogut and Etsion's (KE) rough surface contact model for calculation of the asperity contact pressure. The total friction force was assumed to be the sum of the boundary friction at the contact asperities and the integration of viscous shear stress in the hydrodynamic region. The wear depth on the contact region was estimated according to the modified Archard's wear model using the asperity contact pressure. Sugimura's wear model was modified and used to link the wear particle size distribution and the variation of surface height PDF during wear. In the wear process, the variations of profile and surface height PDF of initial line contacts were calculated step by step in time, and the pressure distribution, friction coefficient, and wear rate were updated consequently. The effect of size distribution of wear particles on the wear process was numerically investigated, and the simulation results showed that the lubrication condition in which small wear particles are generated from the asperity contact region is beneficial to reduce friction coefficient and wear rate, and leads to a better steady mixed lubrication condition.

Fractal characterization of wear particle accumulation in the wear process

Wear ◽  
2001 ◽  
Vol 251 (1-12) ◽  
pp. 1227-1233 ◽  
Author(s):  
Ge Shirong ◽  
Chen Guoan ◽  
Zhang Xiaoyun
Keyword(s):  
Wear Particle ◽  
Wear Process ◽  
Particle Accumulation

A CFD Analysis of the Viscous Fluid Behavior of Glycerin in Various of Stirring Patterns

2016 ◽  
Vol 836 ◽  
pp. 132-138
Author(s):  
Retno Wulandari ◽  
I.N.G. Wardana ◽  
Slamet Wahyudi ◽  
Nurkholis Hamidi
Keyword(s):  
Viscous Fluid ◽  
Computational Fluid Dynamic ◽  
Fluid Dynamic ◽  
Cfd Analysis ◽  
Particle Track ◽  
Streamline Flow ◽  
Flow Topology ◽  
Fluid Behavior ◽  
Simulation Results ◽  
Almost All

The important matter of mixing at both micro and macro-fluidic levels has to be studied for determining how to achieve proper stirring ways. In order to analyse this matter, the first problem was how to visualise and especially how to measure the stirring process in a certain flow. In this study, the behavior of viscous glycerin employing various stirring patterns was investigated. The changes in glycerin solutions were observed by means of streamline flow topology and particle track arising from four variations in configurations: the same stirring directions of rod and vessel (RUN 1), opposite stirring directions of rod and vessel (RUN 2), stationary rod and rotating vessel (RUN 3), stirring rod and stationary vessel (RUN 4). The flow pattern was analyzed with ANSYS computational fluid dynamic tool. The simulation results shows that the opposite direction stirring pattern configuration produced more vortices than those of the same direction stirring patterns and the stirring rod pattern generated more vortices in almost all parts of the vessel than stationary rod pattern.

Sign in / Sign up

Export Citation Format

Share Document