Complementary Approaches for the Numerical Simulation of the Micro-Plasto-Hydrodynamic Lubrication Regime

2015 ◽  
Vol 651-653 ◽  
pp. 492-497 ◽  
Author(s):  
Cédric Hubert ◽  
André Dubois ◽  
Laurent Dubar ◽  
Maxime Laugier ◽  
Nicolas Legrand ◽  
...  
Keyword(s):  
Sheet Metal Forming ◽  
Metal Forming ◽  
Hydrodynamic Lubrication ◽  
Central Element ◽  
Experimental Measurements ◽  
Finite Element Models ◽  
Lubrication Regime ◽  
Lubricant Flow ◽  
Strip Drawing ◽  
Good Agreement

This paper presents recent investigations in the field of lubricant escapes from asperities. This phenomenon, named Micro Plasto Hydrodynamic Lubrication (MPHL), induces friction variation during metal forming processes. A better understanding of MPH lubrication would lead to a better management of friction, which is a central element in most sheet metal forming processes. To fulfil that goal, experiments were conducted in plane strip drawing using a transparent upper tool in order to observe lubricant flow around macroscopic pyramidal cavities. These experiments were then numerically reproduced with two complementary Finite Element models. The numerical results are discussed in this paper and show good agreement with experimental measurements.

scholarly journals Numerical modelling of microscopic lubricant flow in sheet metal forming. Application to plane strip drawing

2017 ◽  
Vol 112 (3) ◽  
pp. 203-237 ◽  
Author(s):  
Y. Carretta ◽  
R. Boman ◽  
J. Bech ◽  
N. Legrand ◽  
M. Laugier ◽  
...  
Keyword(s):  
Numerical Modelling ◽  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Lubricant Flow ◽  
Strip Drawing

scholarly journals Temperature induced friction increase in friction test and forming demonstrator for sheet metal forming

2021 ◽  
Author(s):  
Jan Filzek ◽  
Daniel Keil ◽  
Holger Schröder
Keyword(s):  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Transient Effects ◽  
Friction Test ◽  
Drawing Test ◽  
Machine Operators ◽  
Strip Drawing ◽  
Flat Strip ◽  
The Individual

High process stability is needed in sheet metal forming industry. This can be achieved by predicting and controlling the transient process and temperature variation, especially at start of production. In this connection, the temperature induced friction changing plays a significant role because it leads to product failures. The handling of the transient friction effects is currently done reactively, based on the individual experience of the machine operators. In future, those transient effects need to be controlled. This paper shows initially an analysis of the temperature induced friction increase in a well-known and proven flat strip drawing test. Different tribological systems were tested at tool temperatures between 20 and 80 °C. The temperature increase results in a higher friction of up to 77 %. Several influences on friction increase will be presented. These friction influences were verified afterwards with a heated forming demonstrator under laboratory conditions.

scholarly journals In-situ observation of lubricant flow on laser textured die surface in sheet metal forming

2017 ◽  
Vol 207 ◽  
pp. 2209-2214 ◽  
Author(s):  
Jochen Vorholt ◽  
Tetsuhide Shimizu ◽  
Hiroyuki Kobayashi ◽  
Lukas Heinrich ◽  
Hendrik Flosky ◽  
...  
Keyword(s):  
Sheet Metal ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
In Situ Observation ◽  
Lubricant Flow ◽  
Die Surface

Friction Models for Metal Forming in the Boundary Lubrication Regime

1991 ◽  
Vol 113 (1) ◽  
pp. 60-68 ◽  
Author(s):  
William R. D. Wilson
Keyword(s):  
Boundary Lubrication ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Empirical Equation ◽  
Interface Pressure ◽  
Bulk Forming ◽  
Lubrication Regime ◽  
Friction Models ◽  
Semi Empirical ◽  
Unsteady Conditions

Wilson and Shen’s semi-empirical equation for the effective hardness of a plastically deforming workpiece is used to develop models for tool-workpiece friction in metal-forming processes operating in the boundary lubrication regime. The models treat both steady and unsteady conditions and include the influence of tooling and workpiece topography, sliding speed, interface pressure, and workpiece strain rate on friction. Simplified models are suggested for conditions typical of bulk forming and sheet-metal forming processes.

Multi-scale friction modeling for sheet metal forming: The boundary lubrication regime

2015 ◽  
Vol 81 ◽  
pp. 112-128 ◽  
Author(s):  
J. Hol ◽  
V.T. Meinders ◽  
M.B. de Rooij ◽  
A.H. van den Boogaard
Keyword(s):  
Sheet Metal ◽  
Boundary Lubrication ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Friction Modeling ◽  
Multi Scale ◽  
Lubrication Regime

scholarly journals Revisiting liquid lubrication methods by means of a fully coupled approach combining plastic deformation and liquid lubrication

2017 ◽  
Vol 231 (11) ◽  
pp. 1425-1433
Author(s):  
Esmeray Üstünyagiz ◽  
Peter Christiansen ◽  
Chris V Nielsen ◽  
Niels Bay ◽  
Paulo AF Martins
Keyword(s):  
Plastic Deformation ◽  
Hydrodynamic Lubrication ◽  
Metallic Material ◽  
New Approach ◽  
Drawing Speed ◽  
Lubricant Flow ◽  
Modelling Techniques ◽  
Fully Coupled ◽  
Lubricant Viscosity ◽  
Good Agreement

This paper presents a new approach based on a fully coupled procedure in which the lubricant flow and the plastic deformation of the metallic material in metal forming are solved simultaneously. The proposed method is an alternative to conventional modelling techniques which allow studying the effect of a broad range of parameters directly on the friction conditions. The approach is applied to strip reduction of a sheet with mesoscopic surface pockets in order to investigate the escape of lubricant from the pocket by means of Micro Plasto HydroDynamic Lubrication and Micro Plasto HydroStatic Lubrication. For the investigation on Micro Plasto HydroStatic Lubrication, the friction along the tool–workpiece contact interface and the back tension are taken as parameters, and the backward escape Micro Plasto HydroDynamic Lubrication is investigated by variations in lubricant viscosity by means of a combined numerical and analytical model, and by variations in drawing speed. Good agreement is found with the experimental observations.

Sign in / Sign up

Export Citation Format

Share Document