PERSONAL DE APOYO
MOLINARI Erica Cintia
artículos
Título:
Friction and Wear Behavior of Irradiated Polyethylene Sliding Against a Rough Steel Surface
Autor/es:
WALTER R. TUCKART; ERICA C. MOLINARI; DANIEL ROSSIT; MARCELO D. FAILLA
Revista:
TRIBOLOGY LETTERS
Editorial:
SPRINGER/PLENUM PUBLISHERS
Referencias:
Lugar: Torino; Año: 2014 vol. 55 p. 165 - 176
ISSN:
1023-8883
Resumen:
The aim of this study was to evaluate the tribological
behavior of polyethylene crosslinked by gamma
radiation sliding against a steel surface. Two high-density
polyethylenes were irradiated to a total dose in the range of
2-20 Mrad under vacuum and at room temperature. After
irradiation, the materials were annealed at 423 K and then
cooled slowly to room temperature. The same thermal
treatment was applied to the non-irradiated polymer. The
wear behavior of the polymers was determined under
controlled ambient temperature of 298 and 333 K using a
homemade tribometer. Sheet-shaped specimens were loaded
against the surface of a steel disc with different normal
loads to generate nominal contact pressures in the range of
0.25?1.5 MPa. The tests were performed under dry conditions
using a disc rotation to produce an average sliding
speed of 0.6 m/s and during a period of time to provide an
average sliding distance of 1,080 m. The wear rate was
obtained as the mass loss by the sample divided by the
sliding distance, and the friction coefficient was determined
by measuring the friction force. The results indicate that
the wear rate increases with load in the case of non-irradiated
polyethylene and low-dose irradiated polymers,
while the wear rate reaches a maximum value with the load
in the case of the irradiated samples with high doses. The
samples irradiated with a dose of 10 Mrad showed the
lowest wear. The coefficient of friction (COF) increases slightly with the load in all the cases. Most irradiated
polymers show higher COF than the non-irradiated material
when compared at a given load. The results show that
the irradiation dose applied to the polyethylenes produced
no noticeable effect on the COF values when a comparison
was made at a given applied load.