Tehnički vjesnik, Vol. 19 No. 4, 2012.
Izvorni znanstveni članak
Possibilities to measure contact friction in bulk metal forming
Miroslav Plančak
orcid.org/0000-0001-9035-7879
; Faculty of Technical Science, University of Novi Sad, Trg Dositeja Obradovića 6, 21000 Novi Sad, Serbia
Zlatan Car
orcid.org/0000-0003-2817-9252
; Technical Faculty, University of Rijeka, Vukovarska 58, 51000 Rijeka, Croatia
Marko Kršulja
; Technical Faculty, University of Rijeka, Vukovarska 58, 51000 Rijeka, Croatia
Dragiša Vilotić
; Faculty of Technical Science, University of Novi Sad, Trg Dositeja Obradovića 6, 21000 Novi Sad, Serbia
Igor Kačmarčik
; Faculty of Technical Science, University of Novi Sad, Trg Dositeja Obradovića 6, 21000 Novi Sad, Serbia
Dejan Movrin
orcid.org/0000-0001-7812-0713
; Faculty of Technical Science, University of Novi Sad, Trg Dositeja Obradovića 6, 21000 Novi Sad, Serbia
Sažetak
Friction occurs in all metal forming operations and, in general, it has a negative impact on process parameters, die life, as well as workpiece quality. In cold metal forming processes high interface pressures between die and material take place. These pressures can be the limiting factor of application of cold forming. By reducing interfacial friction, contact pressures can be reduced too. Knowledge of friction amount (factor of friction µ and/or friction ratio m) is essential for calculation of the main process parameters (load, energy), for choosing a proper lubricant but also for numerical modelling of forming operations. There exist a number of experimental methods to determine friction in metal forming processes. Current paper deals with the possibilities to evaluate friction. It analyses and assesses a number of existing friction models in cold metal operations. Proposal of a new friction model for cold metal forming operations is presented and discussed. Measurement of friction force in backward extrusion for different lubrication conditions was also preformed.
Ključne riječi
cold backward extrusion; experimental tooling; friction models
Hrčak ID:
93518
URI
Datum izdavanja:
12.12.2012.
Posjeta: 4.999 *