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4 TRIALS AND RESULTS
Once the textures of the different probes were
obtained, several trials have been carried out in a
Mini Traction Machine from PCS Instruments
(Lafont, 2009), simulating a ball-disc contact, using
a steel ball and the micro-texturized copper discs.
Figure 5 shows the evolution of friction
coefficient as a function of mean velocity (u
m
), for
different diameters of the circular features of the
micro-textured patterns. A smooth disc without
micro-texturization has been used as reference.
Figure 5: Friction reduction by using textured surfaces.
The friction coefficient reduction is specially
noteworthty in the mixed lubrication regime
(u
m
<10
3
mm/s). In addition smaller textures promote
greater reductions of friction, specially for lower
contact velocities.
5 CONCLUSIONS
AND APPLICATIONS
Our results show that the use of very simple micro-
textures helps to improve surface contact behavior
and reduce friction coefficient in the whole mixed
lubrication regime, although additional in vivo
validation needs to be further researched.
Applying this methodology to the contact
surfaces of artificial joint prostheses can help to
obtain low surface roughnesses with micro-textures
acting as reservoirs of lubricant, thus minimizing
friction and improving wear behavior and prostheses
service life. Such textures have also potential
benefits regarding cell growth and tissue formation
besides the prostheses. Future studies will be linked
to the use of end materials and geometries adapted to
those of the different artificial joint prostheses
designs. Industrialization of the proposed process
can be achieved by means of CAD-CAM
technologies, in combination with advanced additive
manufacturing or laser micro-mechanization.
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células y tejidos y método de obtención del mismo.
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Dumbleton, J. H., 1981. Tribology of natural and artificial
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Kennedy, F.E. et al., (2000), Contact fatigue failure of
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Petterson, U., Jacobson, S., (2003). Influence of surface
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Pinchuk, L. S., Nikolaev, V. I., Tsvetkova, E. A., Goldade,
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Stachowiak, G. W., Batchelor, A. W., (2005). Engineering
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Wakuda, M., Yamauchi, Y., Kanzaki, S., Yasuda, Y.,
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lubricated sliding contact. Wear, 254, pp. 356-363.
10
2
10
3
0.02
0.025
0.03
0.035
0.04
u
m
(mm/s)
Effect of textured diameter. W=20N
R=50
μ
m
R=100
μ
m
R=200
μ
m
Smooth
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