Page 7 - PR 2014 2016 10 Materials and Nanotechnology

Materials and Nanotechnology | Progress Report 283

Laser bean marking applied to orthopedic
implant

Laser beam marking is used to ensure the
identification and traceability of biomaterials.
The texturing imparts greater adhesion to the
surfaces of implantable medical devices. The
treatments performed altered the roughness
of the biomaterials as a function of the in-
crease of the pulse frequency (Figure 5)

The microstructure and chemical compo-
sition of the surfaces underwent changes
that directly affected the passive layer of the
stainless steels, favoring the triggering of
the corrosion process. This effect was evi-
denced by SVET, XPS and the characterization
of electronic properties of the passive film.
The parameters used for the marking did not

Figure 6: (a) Regions of the sample-4 analyzed by points and by
line, respectively. The arrow indicates the direction adopted for the
analysis by “line scan”- No attack, (b) On-line mapping of the distri-
bution of the chemical elements present on the sample surface-4, (c)
Marked and standard fractured tensile specimens.

induce a decrease in the cellular viability of
the samples, as no cytotoxicity was showed
even after prolonged incubation. The studied
biomaterial was adequate on the biomechani-
cal tests, since the laser treatments, under the
conditions used, did not induce the formation
of surface tensions of magnitude capable
of leading the fatigue fracture, indicating
infinite fatigue life; the region of fracture by
tension could not be related to the laser mark-
ing (Figure 6c). The wear volume decreased as
a function of the increase in micro hardness
produced by the increase of the pulse frequen-
cy in the texturing. The visual character of the
markings and texturing was assured after the
majority of the tests performed.
Figure 5: Topography of (a) untreated and (b) textured laser
biomaterials