scholarly journals Pressure and sliding velocity dependent surface asperity based friction model: Application to springback simulation

2019 ◽  
Vol 651 ◽  
pp. 012079
Author(s):  
K J Lee ◽  
M G Lee
Keyword(s):  
Friction Model ◽  
Sliding Velocity ◽  
Model Application ◽  
Surface Asperity

Viscous Friction Effect During the Process of Tightening and Loosening of Bolted Joints

2021 ◽  
Author(s):  
Qingyuan Lin ◽  
Yong Zhao ◽  
Qingchao Sun ◽  
Kunyong Chen
Keyword(s):  
Friction Coefficient ◽  
Viscous Friction ◽  
Normal Pressure ◽  
Friction Model ◽  
Bolted Joints ◽  
Critical Parameters ◽  
Bolted Joint ◽  
Sliding Velocity ◽  
Friction Effect ◽  
Bearing Friction

Abstract Bolted connection is one of the most widely used mechanical connections because of its easiness of installation and disassembly. Research of bolted joints mainly focuses on two aspects: high precision tightening and improvement of anti-loosening performance. The under-head bearing friction coefficient and the thread friction coefficient are the two most important parameters that affect the tightening result of the bolted joint. They are also the most critical parameters that affect the anti-loosening performance of the bolted joint. Coulomb friction model is a commonly used model to describe under-head bearing friction and thread friction, which considers the friction coefficient as a constant independent of normal pressure and relative sliding velocity. In this paper, the viscous effect of the under-head bearing friction and thread friction is observed by measuring the friction coefficient of bolted joints. The value of the friction coefficient increases with the increase of the relative sliding velocity and the decrease of the normal pressure. It is found that the Coulomb viscous friction model can better describe the friction coefficient of bolted joints. Taking into account the dense friction effect, the loosening prediction model of bolted joints is modified. The experimental results show that the Coulomb viscous friction model can better describe the under-head bearing friction coefficient and thread friction coefficient. The model considering the dense effect can more accurately predict the loosening characteristics of bolted joints.

Identification of a Friction Model at the Tool-Chip-Workpiece Interface in Dry Machining of a AISI 1045 Steel With a TiN Coated Carbide Tool

2011 ◽  
Vol 133 (4) ◽  
Author(s):  
Hamdi Ben Abdelali ◽  
Cedric Courbon ◽  
Joël Rech ◽  
Wacef Ben Salem ◽  
Abdelwaheb Dogui ◽  
...  
Keyword(s):  
Friction Model ◽  
Carbide Tool ◽  
Dry Machining ◽  
Sliding Velocity ◽  
Partition Model ◽  
Heat Partition ◽  
Aisi 1045 Steel ◽  
Aisi 1045 ◽  
1045 Steel ◽  
Coated Carbide

The characterization of frictional phenomena at the tool-chip-workpiece interface in metal cutting remains a challenge. This paper aims at identifying a friction model and a heat partition model at this interface during the dry cutting of an AISI1045 steel with TiN coated carbide tools. A new tribometer, based on a modified pin-on-ring system, has been used in order to reach relevant values of pressures, temperatures, and sliding velocities. Additionally a 3D Arbitrary Lagrangian Eulerian model (A.L.E.) numerical model simulating the frictional test has been developed in order to extract local parameters around the spherical pin, such as average contact pressure, average local sliding velocity, and average contact temperature, from experimental macroscopic measurements. A large range of sliding velocities [0.083–5 m/s] has been investigated. It has been shown that friction coefficient and heat partition coefficient are mainly dependant on local sliding velocity at the interface. Three friction regimes have been identified. These experimental and numerical results provide a better understanding of the tribological phenomena along the tool-chip-workpiece interfaces in dry machining of an AISI 1045 steel with a TiN coated carbide tool. Finally a new friction model and heat partition model has been developed for implementation in a numerical cutting model.

A Novel Dynamic Friction Model Based on Asperity Creep

2008 ◽  
Author(s):  
Andreas Goedecke ◽  
Randolf Mock
Keyword(s):  
Friction Coefficient ◽  
Rough Surfaces ◽  
Fractal Model ◽  
Friction Model ◽  
Test Case ◽  
Dynamic Friction ◽  
Surface Asperity ◽  
Perfectly Plastic ◽  
Novel Approach ◽  
Asperity Model

We present a novel approach for the simulation of dynamic friction in engineering systems, based on a new surface asperity model including creep effects. Our novel friction model aims at understanding the link between the microscopic origins of friction dynamics and the response of the engineering-level friction induced vibrations. The approach is based on the assumption that the time- and velocity-dependent friction coefficient is mainly caused by creep growth of surface asperity contacts (microscopic contact patches between two rough surfaces) as proposed by Kragelskii, Rabinowicz, Scholz and others. At the heart of our approach is a new asperity model that includes creep effects. Based on the pioneering work of Etsion et al., we conducted extensive FEM simulations to analyze the creep behavior of an elastic-perfectly plastic hemisphere in contact with a rigid flat. The new asperity model is used as a building block for a fractal model for the contact between rough surfaces. The model yields the time- and velocity-dependent macroscopic friction coefficient. We demonstrate the practical applicability of the new dynamic friction model in a simple block-on-conveyor test case to analyze friction induced vibrations.

Application of subloading-overstress friction model to finite element analysis

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
T. Kuwayama ◽  
K. Hashiguchi ◽  
N. Suzuki ◽  
N. Yoshinaga ◽  
S. Ogawa
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Flat Surface ◽  
Surface Friction ◽  
Friction Model ◽  
Sliding Velocity ◽  
Element Analysis ◽  
Contact Behaviour ◽  
Wide Range ◽  
The Finite Element Analysis

Accurate prediction of contact behaviour between machine tools and metals is required for the mechanical design of machinery. In this article, the numerical analysis of the contact behaviour is described by incorporating the subloading-overstress model [6] which is capable of describing the contact behaviour for a wide range of sliding velocity including the increase of coefficient of friction with the increase of sliding velocity. And its validity is verified by the comparison with some test results. First, in order to examine the influence of sliding velocities on the friction properties, the flat-surface friction tests for lubricated interfaces between galvannealed steel sheet and SKD-11 tool steel were performed. As a result, It is observed that the friction smoothly translate to kinetic friction, after exhibiting the peak at the static friction. In addition, it is observed that the higher the sliding velocity, the larger the friction resistance, meaning the positive rate sensitivity. Then the subloading-overstress model is implemented in the finite element analysis program ABAQUS/Standard, and it is used to simulate the flat-surface friction tests. The predictions from the finite element analysis are shown to be in very good agreement with experimental results.

scholarly journals Constitutive equation of friction based on the subloading-surface concept

2016 ◽  
Vol 472 (2191) ◽  
pp. 20160212 ◽  
Author(s):  
Koichi Hashiguchi ◽  
Masami Ueno ◽  
Takuya Kuwayama ◽  
Noriyuki Suzuki ◽  
Shigeru Yonemura ◽  
...  
Keyword(s):  
Rate Sensitivity ◽  
Steel Specimen ◽  
Static Friction ◽  
Friction Model ◽  
Smooth Transition ◽  
Kinetic Friction ◽  
Sliding Velocity ◽  
Friction Resistance ◽  
Negative Rate ◽  
Positive Rate

The subloading-friction model is capable of describing static friction, the smooth transition from static to kinetic friction and the recovery to static friction after sliding stops or sliding velocity decreases. This causes a negative rate sensitivity (i.e. a decrease in friction resistance with increasing sliding velocity). A generalized subloading-friction model is formulated in this article by incorporating the concept of overstress for viscoplastic sliding velocity into the subloading-friction model to describe not only negative rate sensitivity but also positive rate sensitivity (i.e. an increase in friction resistance with increasing sliding velocity) at a general sliding velocity ranging from quasi-static to impact sliding. The validity of the model is verified by numerical experiments and comparisons with test data obtained from friction tests using a lubricated steel specimen.

On the Modeling of Quasi-Steady and Unsteady Dynamic Friction in Sliding Lubricated Line Contact

2009 ◽  
Vol 132 (1) ◽  
Author(s):  
H. Sojoudi ◽  
M. M. Khonsari
Keyword(s):  
Experimental Data ◽  
Friction Coefficient ◽  
Reynolds Equation ◽  
Friction Model ◽  
Sliding Contact ◽  
Dynamic Friction ◽  
Line Contact ◽  
Sliding Velocity ◽  
Friction Behavior ◽  
Lubricated Sliding

A simple but realistic dynamic friction model for the lubricated sliding contact is developed based on decoupling the steady and unsteady terms in Reynolds equation. The model realistically captures the physics of friction behavior both when speed is increased unidirectionally or when operating under oscillating condition. The model can simulate the transition from boundary to mixed to full film regimes as the speed is increased. Two different classes of simulations are performed to show the utility of the model: the so-called quasisteady, where the sliding velocity is varied very slowly, and the oscillating sliding velocity, where the friction coefficient exhibits a hysteresis type behavior. Both categories of simulation are verified by comparing the results with published experimental data.

A Two-Component Mixed Friction Model for a Lubricated Line Contact

1996 ◽  
Vol 118 (1) ◽  
pp. 183-189 ◽  
Author(s):  
A. A. Polycarpou ◽  
A. Soom
Keyword(s):  
Normal Load ◽  
Friction Model ◽  
Time Varying ◽  
Line Contact ◽  
Sliding Velocity ◽  
Fluid Shear ◽  
Lubrication Regimes ◽  
Two Component ◽  
Fluid Properties ◽  
Solid Friction

A two-component, two-dimensional friction model for a lubricated line contact, operating in boundary and mixed lubrication regimes, is developed. The friction is explicitly decomposed into the solid and the fluid shear components. The solid component is due to the asperity interactions and the fluid shear arises from the lubricant present at the interface. The friction model includes the sliding velocity, the instantaneous separation of the sliding bodies, normal to the sliding direction, the normal load and fluid properties. The model is based on unsteady friction experiments carried out under constant normal loads and time-varying sliding velocities. The model is applied to quasi-steady sliding, unsteady continuous and intermittent sliding, including sticking and momentary reversals of motion. In each case it becomes possible to track the instantaneous fluid shear and solid friction components.

Cutting performance investigation based on the variable friction model by considering sliding velocity and limiting stress

2020 ◽  
Vol 234 (8) ◽  
pp. 1113-1123
Author(s):  
Xin Li ◽  
Zhenyu Shi ◽  
Ningmin Duan ◽  
Peng Cui ◽  
Shuai Zhang ◽  
...  
Keyword(s):  
Finite Element ◽  
Friction Coefficient ◽  
Finite Element Model ◽  
Cutting Force ◽  
Element Model ◽  
Friction Model ◽  
Rake Face ◽  
Sliding Velocity ◽  
Variable Friction ◽  
Simulation Results

Fast and accurate cutting force prediction is still one of the most complex problems and challenges in the machining research community. In this study, a modified finite element model is presented to predict cutting force and cutting length in turning operations of AISI 1018. Unlike the existing research, in which the mean friction coefficient μ was taken, a variable friction coefficient μ involving the sliding velocity between chip and tool is presented in this article. The sticking–sliding friction model is adopted, and the maximum limiting stress in sticking region is calculated by considering the thermal softening and normal stress distribution. Experiments have been performed for machining AISI 1018 using tungsten carbide tool, and simulation results have been compared to experiments. The simulation results of the modified finite element model have shown better outputs in predicting cutting force, tangential force, and tool–chip contact length on the rake face. The results of this article not only are meaningful to optimize tool design and cutting parameters but also can provide a clear understanding of contact behavior between tool rake face and chip.

Sign in / Sign up

Export Citation Format

Share Document