Simulation of Dynamic Lubricant Effects in Sheet Metal Forming Processes

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Tribology plays an important role in sheet metal forming processes relating to near net shape production processes and achievable surface qualities. Nearly every process is realized by using characteristic lubricants affecting the tribological system to achieve the desired results. Deterministic structures on sheet surfaces can result in less friction and higher drawing ratios. This is caused by hydrostatic pressures build up in closed lubricant areas and hydrodynamic pressures due to the lubricant motion especially in thin fluid films [1, 2, 3]. Friction mechanisms in the mixed lubrication regime are not fully understood till today. The numerical simulation of flows in lubricant pockets and their influence on surface evolution are promising ways to gain more knowledge of the lubricant behavior in tribological systems. Therefore, this paper shows results of combined numerical and experimental approaches. The described simulations of closed lubricant pockets on surfaces identify influencing parameters. Strip drawing experiments are done to verify the simulations. The influence and the importance of local pressures due to viscous effects in the lubricant are considered as well as the necessity to use fluid-structure-interactions to simulate the behavior of lubricants in the tribological system.

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Periodical:

Edited by:

M. Merklein, F.-W. Bach, K.-D. Bouzakis, B. Denkena, M. Geiger and H.-K. Toenshoff

Pages:

171-178

DOI:

10.4028/www.scientific.net/KEM.438.171

Citation:

M. Ludwig et al., "Simulation of Dynamic Lubricant Effects in Sheet Metal Forming Processes", Key Engineering Materials, Vol. 438, pp. 171-178, 2010

Online since:

May 2010

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$35.00

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